ORACLE 12C – 第2页 – Database SOS

18c新特性：Scalable Sequences(自适应序列)

作为18c的新特性,其实在oracle 12.2 引入了Scalable Sequences作为一个隐藏特性，为了改善在高并发系统中，特别是使用seq作为index，大量插入记录导致index的争用，oracle自己实现了以前我们需要人工去自定义seq的方式(instance+sid+seq的类似算法方式）,该功能将在oracle 18c中正式推出,我这里带领大家先体会下
SCALE/NOSCALE
When SCALE is specified, a numeric offset is affixed to the beginning of the sequence. This offset if of the form iii||sss||, where,
iii denotes a three digit instance offset given by (instance_id % 100) + 100,
sss denotes a three digits session offset given by (session_id % 1000), and
|| is the concatenation operator

EXTEND/NOEXTEND
When EXTEND is specified with the SCALE keyword, the generated sequence values are all of length (x+y), where x is the length of the scalable offset (default 6), and y is the maximum number of digits in the sequence maxvalue/minvalue. Thus, for an ascending sequence with maxvalue 100 and SCALABLE EXTEND specified, the generated sequence values are of the form iii||sss||001, iii||sss||002, …,iii||sss||100
The default setting for the SCALE clause is NOEXTEND. With the NOEXTEND setting, the generated sequence values are at most as wide as the maximum number of digits in the sequence maxvalue/minvalue. This setting is useful for integration with existing applications where sequences are used to populate fixed width columns. On invocation of NEXTVAL on a sequence with SCALABLE NOEXTEND specified, a user error is thrown if the generated value requires more digits of representation than the sequence’s maxvalue/minvalue.

SCALE的算法就是(instance_id % 100)(_kqdsn_instance_digits) + 100||(session_id % 1000)(_kqdsn_cpu_digits)+seq(EXTEND/NOEXTEND确定是否固定宽度）

Scalable Sequences语法

CREATE | ALTER SEQUENCE [ schema. ]sequence
[ { INCREMENT BY | START WITH } integer
| { MAXVALUE integer | NOMAXVALUE }
| { MINVALUE integer | NOMINVALUE }
| { CYCLE | NOCYCLE }
| { CACHE integer | NOCACHE }
| { ORDER | NOORDER }
| { SCALE {EXTEND | NOEXTEND} | NOSCALE}
]

Scalable Sequences测试

[oracle@xifenfei ~]$ sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Tue Jan 23 02:33:49 2018
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
BANNER                                                                               CON_ID
-------------------------------------------------------------------------------- ----------
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production              0
PL/SQL Release 12.2.0.1.0 - Production                                                    0
CORE    12.2.0.1.0      Production                                                        0
TNS for Linux: Version 12.2.0.1.0 - Production                                            0
NLSRTL Version 12.2.0.1.0 - Production                                                    0
SQL> set line 150
SQL> col "Paramete"  for a30
SQL> col "Session Value"  for a20
SQL> col "Instance Value" for a20
SQL> col "Is Default?" for a20
SQL> SELECT a.ksppinm "Parameter", b.ksppstvl "Session Value", c.ksppstvl "Instance Value",c.ksppstdf "Default?"
  2  FROM x$ksppi a, x$ksppcv b, x$ksppsv c WHERE a.indx = b.indx  AND a.indx = c.indx  AND lower(a.ksppinm)
  3  in ('_kqdsn_instance_digits', '_kqdsn_cpu_digits');
Parameter                                                Session Value        Instance Value       Default?
-------------------------------------------------------- -------------------- -------------------- ---------
_kqdsn_instance_digits                                   2                    2                    TRUE
_kqdsn_cpu_digits                                        3                    3                    TRUE
SQL> select instance_number from v$instance;
INSTANCE_NUMBER
---------------
              1
SQL> select sys_context('userenv','sid') from dual;
SYS_CONTEXT('USERENV','SID')
----------------------------------------------------------------------------
275
SQL> create sequence seq_xff start with 1 increment by 1 minvalue 1 maxvalue 100 scale extend;
Sequence created.
SQL> select seq_xff.nextval from dual;
   NEXTVAL
----------
 101275001

验证效果

--另外一个会话
[oracle@xifenfei ~]$ sqlplus / as sysdba
SQL*Plus: Release 12.2.0.1.0 Production on Tue Jan 23 02:45:14 2018
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> select sys_context('userenv','sid') from dual;
SYS_CONTEXT('USERENV','SID')
---------------------------------------------------------
4
SQL> select instance_number from v$instance;
INSTANCE_NUMBER
---------------
              1
SQL> select seq_xff.nextval from dual;
   NEXTVAL
----------
 101004002

这里可以看出来seq的值是固定长度的.而且随着sid或者inst_id 不同而不同,从而实现减少大量数据集中在一个block而引起的各种争用
测试scale noextend

SQL> create sequence seq_xifenfei start with 1 increment by 1 minvalue 1 maxvalue 100 scale noextend;
Sequence created.
SQL> select seq_xifenfei.nextval from dual;
select seq_xifenfei.nextval from dual
       *
ERROR at line 1:
ORA-64603: NEXTVAL cannot be instantiated for seq_xifenfei. Widen the sequence
by 4 digits or alter sequence with SCALE EXTEND.
SQL> drop sequence seq_xifenfei;
Sequence dropped.
SQL> create sequence seq_xifenfei start with 1 increment by 1 minvalue 1 maxvalue 1000000 scale noextend;
Sequence created.
SQL>  select seq_xifenfei.nextval from dual;
   NEXTVAL
----------
   1010041

这里可以看出来scale noextend的长度是随着seq值的改变而改变,而且max值不能小于seq本身长度.

ORA-20001: Latest xml inventory is not loaded into table

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：ORA-20001: Latest xml inventory is not loaded into table

12.2数据库启动报ORA-20001错

2018-01-22T04:51:19.574350-05:00
Unable to obtain current patch information due to error: 20001,
  ORA-20001: Latest xml inventory is not loaded into table
ORA-06512: at "SYS.DBMS_QOPATCH", line 777
ORA-06512: at "SYS.DBMS_QOPATCH", line 864
ORA-06512: at "SYS.DBMS_QOPATCH", line 2222
ORA-06512: at "SYS.DBMS_QOPATCH", line 740
ORA-06512: at "SYS.DBMS_QOPATCH", line 2247
===========================================================
Dumping current patch information
===========================================================
Unable to obtain current patch information due to error: 20001
===========================================================

patch日志

KUP-05007:   Warning: Intra source concurrency disabled because the preprocessor option is being used.
Field Definitions for table OPATCH_XML_INV
  Record format DELIMITED BY NEWLINE
  Data in file has same endianness as the platform
  Reject rows with all null fields
  Fields in Data Source:
    XML_INVENTORY                   CHAR (100000000)
      Terminated by "UIJSVTBOEIZBEFFQBL"
      Trim whitespace same as SQL Loader

DBMS_QOPATCH包是提供PLSQL/SQL接口方式访问数据库补丁安装情况，oracle在启动的时候会去调用这个包查询patch情况，由于ORA-20001 Latest XML inventory is not loaded into table.导致失败，从而出现上述启动错误。
主要相关的sql

CREATE OR REPLACE DIRECTORY "OPATCH_LOG_DIR" AS '/u01/app/oracle/product/11.2.0/dbhome_1/QOpatch';
CREATE OR REPLACE DIRECTORY "OPATCH_SCRIPT_DIR" AS '/u01/app/oracle/product/11.2.0/dbhome_1/QOpatch';
CREATE TABLE "SYS"."OPATCH_XML_INV"
   (    "XML_INVENTORY" CLOB
   )
   ORGANIZATION EXTERNAL
    ( TYPE ORACLE_LOADER
      DEFAULT DIRECTORY "OPATCH_SCRIPT_DIR"
      ACCESS PARAMETERS
      ( RECORDS DELIMITED BY NEWLINE CHARACTERSET UTF8
      DISABLE_DIRECTORY_LINK_CHECK
      READSIZE 8388608
      preprocessor opatch_script_dir:'qopiprep.bat'
      BADFILE opatch_script_dir:'qopatch_bad.bad'
      LOGFILE opatch_log_dir:'qopatch_log.log'
      FIELDS TERMINATED BY 'UIJSVTBOEIZBEFFQBL'
      MISSING FIELD VALUES ARE NULL
      REJECT ROWS WITH ALL NULL FIELDS
      (
        xml_inventory    CHAR(100000000)
      )
        )
      LOCATION
       ( "OPATCH_SCRIPT_DIR":'qopiprep.bat'
       )
    )
   REJECT LIMIT UNLIMITED;

解决方案

---方案1
SQL> alter system set "_disable_directory_link_check"=true scope=spfile;
System altered.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 2432696320 bytes
Fixed Size                  8795664 bytes
Variable Size             654313968 bytes
Database Buffers         1761607680 bytes
Redo Buffers                7979008 bytes
Database mounted.
Database opened.
SQL> SELECT a.ksppinm "Parameter",
  2  b.ksppstvl "Session Value",
  3  c.ksppstvl "Instance Value"
  4  FROM x$ksppi a,
  5  x$ksppcv b,
  6  x$ksppsv c
  7  WHERE a.indx = b.indx
  8  AND a.indx = c.indx
  9  AND a.ksppinm LIKE '/_disable_direc%' escape '/' ;
Parameter
--------------------------------------------------------------------------------
Session Value
--------------------------------------------------------------------------------
Instance Value
--------------------------------------------------------------------------------
_disable_directory_link_check
TRUE
TRUE
SQL> exit
$ORACLE_HOME/sqlpatch/datapatch
---方案2
SQL> create or replace directory OPATCH_LOG_DIR as '<complete path to QOpatch>';
Directory created.
SQL> create or replace directory OPATCH_SCRIPT_DIR as '<complete path to QOpatch>';
Directory created.
---方案3
cd $ORACLE_HOME/sqlpatch
./datapatch -verbose
---方案4
chmod 775 -r $ORACLE_HOME/rdbms/log
$ORACLE_HOME/OPatch/datapatch -prereq

参考MOS
Queryable Patch Inventory – Issues/Solutions for ORA-20001: Latest xml inventory is not loaded into table (Doc ID 1602089.1)
12.2:DB Alert.log shows ORA-20001: Latest xml inventory,ORA-06512: at “SYS.DBMS_QOPATCH”,”KUP-04004: error while reading file” (Doc ID 2323937.1)

Oracle 12c active dataguard switchover

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：Oracle 12c active dataguard switchover

从12.1开始adg的切换发生了一些改变,直接使用alter database switchover to [target standby db_unique_name] verify; alter database switchover to [target standby db_unique_name]; 即可完成切换,以下是一次生产环境的具体操作步骤
主库操作

SQL> select database_role from v$database;
DATABASE_ROLE
----------------
PRIMARY
SQL> alter database switchover to xifenfei verify;
数据库已更改。
--alert日志
Sun Jun 25 09:07:08 2017
diag_adl:SWITCHOVER VERIFY: Send VERIFY request to switchover target xifenfei
diag_adl:SWITCHOVER VERIFY COMPLETE
SQL> alter database switchover to xifenfei;
数据库已更改。
--alert日志
Sun Jun 25 09:07:46 2017
diag_adl:Starting switchover [Process ID: 37024]
Sun Jun 25 09:07:46 2017
diag_adl:ALTER DATABASE COMMIT TO SWITCHOVER TO PHYSICAL STANDBY [Process Id: 37024] (xifenfei)
diag_adl:Waiting for target standby to receive all redo
Sun Jun 25 09:07:46 2017
diag_adl:Waiting for all non-current ORLs to be archived...
Sun Jun 25 09:07:46 2017
diag_adl:All non-current ORLs have been archived.
Sun Jun 25 09:07:46 2017
diag_adl:Waiting for all FAL entries to be archived...
Sun Jun 25 09:07:46 2017
diag_adl:All FAL entries have been archived.
Sun Jun 25 09:07:46 2017
diag_adl:Waiting for dest_id 2 to become synchronized...
Sun Jun 25 09:07:47 2017
diag_adl:Active, synchronized Physical Standby switchover target has been identified
diag_adl:Preventing updates and queries at the Primary
diag_adl:Generating and shipping final logs to target standby
diag_adl:Switchover End-Of-Redo Log thread 1 sequence 96534 has been fixed
diag_adl:Switchover: Primary highest seen SCN set to 0x3.0x109d7502
diag_adl:ARCH: Noswitch archival of thread 1, sequence 96534
diag_adl:ARCH: End-Of-Redo Branch archival of thread 1 sequence 96534
diag_adl:ARCH: LGWR is scheduled to archive destination LOG_ARCHIVE_DEST_2 after log switch
diag_adl:ARCH: Standby redo logfile selected for thread 1 sequence 96534 for destination LOG_ARCHIVE_DEST_2
diag_adl:ARCH: Archiving is disabled due to current logfile archival
diag_adl:Primary will check for some target standby to have received all redo
diag_adl:Waiting for target standby to apply all redo
diag_adl:Backup controlfile written to trace file
            /u01/app/oracle/diag/rdbms/xifenfeildg/xifenfei/trace/xifenfei_ora_37024.trc
diag_adl:Converting the primary database to a new standby database
diag_adl:Clearing standby activation ID 612004791 (0x247a73b7)
diag_adl:The primary database controlfile was created using the
diag_adl:'MAXLOGFILES 16' clause.
diag_adl:There is space for up to 11 standby redo logfiles
diag_adl:Use the following SQL commands on the standby database to create
diag_adl:standby redo logfiles that match the primary database:
diag_adl:ALTER DATABASE ADD STANDBY LOGFILE 'srl1.f' SIZE 1073741824;
diag_adl:ALTER DATABASE ADD STANDBY LOGFILE 'srl2.f' SIZE 1073741824;
diag_adl:ALTER DATABASE ADD STANDBY LOGFILE 'srl3.f' SIZE 1073741824;
diag_adl:ALTER DATABASE ADD STANDBY LOGFILE 'srl4.f' SIZE 1073741824;
diag_adl:ALTER DATABASE ADD STANDBY LOGFILE 'srl5.f' SIZE 1073741824;
diag_adl:ALTER DATABASE ADD STANDBY LOGFILE 'srl6.f' SIZE 1073741824;
diag_adl:Archivelog for thread 1 sequence 96534 required for standby recovery
diag_adl:Switchover: Primary controlfile converted to standby controlfile succesfully.
diag_adl:Switchover: Complete - Database shutdown required
diag_adl:Sending request(convert to primary database) to switchover target xifenfei
Sun Jun 25 09:07:58 2017
diag_adl:Switchover complete. Database shutdown required
diag_adl:USER (ospid: 37024): terminating the instance
Sun Jun 25 09:07:59 2017
diag_adl:Instance terminated by USER, pid = 37024
diag_adl:Shutting down instance (abort)
diag_adl:License high water mark = 527
Sun Jun 25 09:07:59 2017
Instance shutdown complete

备库alert日志

Sun Jun 25 09:05:54 2017
SWITCHOVER VERIFY BEGIN
SWITCHOVER VERIFY COMPLETE
Sun Jun 25 09:06:35 2017
RFS[107]: Assigned to RFS process (PID:7330)
RFS[107]: Selected log 12 for thread 1 sequence 96534 dbid 588725663 branch 916962073
Sat Jun 24 20:06:35 2017
Archived Log entry 100576 added for thread 1 sequence 96534 ID 0x247a73b7 dest 1:
Sat Jun 24 20:06:35 2017
Resetting standby activation ID 612004791 (0x247a73b7)
Sat Jun 24 20:06:35 2017
Media Recovery End-Of-Redo indicator encountered
Sat Jun 24 20:06:35 2017
Media Recovery Continuing
Media Recovery Waiting for thread 1 sequence 96535
Sun Jun 25 09:06:36 2017
SWITCHOVER: received request 'ALTER DTABASE COMMIT TO SWITCHOVER  TO PRIMARY' from primary database.
Sun Jun 25 09:06:36 2017
ALTER DATABASE SWITCHOVER TO PRIMARY (xifenfei)
Maximum wait for role transition is 15 minutes.
Switchover: Media recovery is still active
Role Change: Canceling MRP - no more redo to apply
Sat Jun 24 20:06:36 2017
MRP0: Background Media Recovery cancelled with status 16037
Sat Jun 24 20:06:36 2017
Errors in file /u01/app/oracle/diag/rdbms/xifenfei/xifenfei/trace/xifenfei_pr00_4590.trc:
ORA-16037: user requested cancel of managed recovery operation
Managed Standby Recovery not using Real Time Apply
Recovery interrupted!
Sat Jun 24 20:06:36 2017
Errors in file /u01/app/oracle/diag/rdbms/xifenfei/xifenfei/trace/xifenfei_pr00_4590.trc:
ORA-16037: user requested cancel of managed recovery operation
Sat Jun 24 20:06:37 2017
MRP0: Background Media Recovery process shutdown (xifenfei)
Sun Jun 25 09:06:38 2017
Role Change: Canceled MRP
Killing 2 processes(PIDS:7328,4704)(all RFS)
      in order to disallow current and future RFS connections.Requested by OS process 7334
Stopping Emon pool
All dispatchers and shared servers shutdown
CLOSE: killing server sessions.
Active process 5428 user 'oracle' program 'oracle@kage7.hk0620.com (TNS V1-V3)'
Active process 5161 user 'oracle' program 'oracle@kage7.hk0620.com'
…………
Active process 5428 user 'oracle' program 'oracle@kage7.hk0620.com (TNS V1-V3)'
Active process 5161 user 'oracle' program 'oracle@kage7.hk0620.com'
Active process 5178 user 'oracle' program 'oracle@kage7.hk0620.com'
CLOSE: all sessions shutdown successfully.
Stopping Emon pool
Sat Jun 24 20:06:43 2017
SMON: disabling cache recovery
Sat Jun 24 20:06:44 2017
Buffer Cache Full DB Caching mode changing from FULL CACHING DISABLED to FULL CACHING ENABLED
Sun Jun 25 09:06:44 2017
Backup controlfile written to trace file /u01/app/oracle/diag/rdbms/xifenfei/xifenfei/trace/xifenfei_rmi_7334.trc
SwitchOver after complete recovery through change 13163656450
Online logfile pre-clearing operation disabled by switchover
Online log /u01/app/oracle/oradata/xifenfei/redo01n.log: Thread 1 Group 1 was previously cleared
Online log /u01/app/oracle/fast_recovery_area/xifenfei/redo01n.log: Thread 1 Group 1 was previously cleared
Online log /u01/app/oracle/oradata/xifenfei/redo02n.log: Thread 1 Group 2 was previously cleared
Online log /u01/app/oracle/fast_recovery_area/xifenfei/redo02n.log: Thread 1 Group 2 was previously cleared
Online log /u01/app/oracle/oradata/xifenfei/redo03n.log: Thread 1 Group 3 was previously cleared
Online log /u01/app/oracle/fast_recovery_area/xifenfei/redo03n.log: Thread 1 Group 3 was previously cleared
Online log /u01/app/oracle/oradata/xifenfei/redo04n.log: Thread 1 Group 4 was previously cleared
Online log /u01/app/oracle/fast_recovery_area/xifenfei/redo04n.log: Thread 1 Group 4 was previously cleared
Online log /u01/app/oracle/oradata/xifenfei/redo05n.log: Thread 1 Group 5 was previously cleared
Online log /u01/app/oracle/fast_recovery_area/xifenfei/redo05n.log: Thread 1 Group 5 was previously cleared
Standby became primary SCN: 13163656448
Switchover: Complete - Database mounted as primary
SWITCHOVER: completed request from primary database.
Sat Jun 24 20:07:12 2017
ARC0: Becoming the 'no SRL' ARCH

原备库(现主库)操作

SQL> conn / as sysdba
Connected.
SQL>  select database_role,open_mode from v$database;
DATABASE_ROLE    OPEN_MODE
---------------- --------------------
PRIMARY          MOUNTED
SQL> alter database open;
Database altered.

原主库(现备库)操作

[oracle@localhost scripts]$ ss
SQL*Plus: Release 12.1.0.2.0 Production on 星期日 6月 25 09:09:40 2017
Copyright (c) 1982, 2014, Oracle.  All rights reserved.
已连接到空闲例程。
SQL> startup
ORACLE 例程已经启动。
Total System Global Area 8.5899E+10 bytes
Fixed Size                  7654304 bytes
Variable Size            1.2616E+10 bytes
Database Buffers         7.3014E+10 bytes
Redo Buffers              260780032 bytes
数据库装载完毕。
数据库已经打开。
SQL> alter database recover managed standby database disconnect;
数据库已更改。

Physically Addressed Metadata Redundancy on 12c ASM ( PHYS_META_REPLICATED )

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：Physically Addressed Metadata Redundancy on 12c ASM ( PHYS_META_REPLICATED )

从版本12.1开始，ASM会对某些物理元数据做一份复制，具体的说是每个磁盘的第一个AU（0号AU）上元数据。这意味着，ASM同时维护着两份磁盘头、FST（Free Space Table）表、AT（Allocation table）表的数据。需要注意的是ASM对这些数据采用的是复制（replicate），而不是镜像（mirror）。ASM镜像（mirror）意味着把一份数据，拷贝到不同磁盘上；而物理元数据的副本位于相同的磁盘，因此使用的术语复制（replicate）。这意味着在external冗余的磁盘组中，物理元数据也会被复制。PST也是物理元数据，但是ASM是通过镜像，而不是复制来提供数据保护。因此只有在normal和high冗余的磁盘组中，PST表存在数据的冗余。物理元数据位于每块ASM磁盘的0号AU。元数据复制的特性打开后，ASM会把0号AU的内容拷贝到11号AU，然后同时维护这两份副本。创建磁盘组时如果指定或修改了一个已经存在的磁盘组的compatibility属性为12.1及以上，该特性会自动被打开。当提升ASM compatibility属性值为12.1及以上时，如果11号AU有数据，ASM将把这些数据移动到别处，然后将物理元数据复制到11号AU。从版本11.1.0.7开始，ASM在1号AU的倒数第二个块维护了一份磁盘头的副本。在版本12.1中，ASM仍然维护着这个副本数据。也就是说，现在每个ASM磁盘，有磁盘头的三个副本。
au 0中具体数据

命令行创建diskgroup

[grid@localhost ~]$ sqlplus / as sysasm
SQL*Plus: Release 12.2.0.1.0 Production on Sat Apr 22 08:13:31 2017
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> create diskgroup xifenfei  external redundancy disk '/dev/xifenfei-sdg','/dev/xifenfei-sdh';
Diskgroup created.
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production

查看xifenfei磁盘组属性

[grid@localhost ~]$ asmcmd lsattr -l -G XIFENFEI
Name                     Value
access_control.enabled   FALSE
access_control.umask     066
au_size                  1048576
cell.smart_scan_capable  FALSE
compatible.asm           11.2.0.2.0
compatible.rdbms         10.1.0.0.0
disk_repair_time         3.6h
idp.boundary             auto
idp.type                 dynamic
sector_size              512

这里可以看到目前compatible.asm为11.2,没有phys_meta_replicated属性

查看磁盘头信息
ASM磁盘头的fdhdb.flags条目指代了物理元数据的复制状态：
· kfdhdb.flags = 0 — 元数据没有复制
· kfdhdb.flags = 1 — 元数据已经复制完毕
· kfdhdb.flags = 2 — 元数据在复制过程中

[grid@localhost ~]$ for disk in `asmcmd lsdsk -G XIFENFEI --suppressheader`;
> do kfed read $disk | egrep "dskname|flags"; done
kfdhdb.dskname:           XIFENFEI_0000 ; 0x028: length=13
kfdhdb.flags:                         0 ; 0x0fc: 0x00000000
kfdhdb.dskname:           XIFENFEI_0001 ; 0x028: length=13
kfdhdb.flags:                         0 ; 0x0fc: 0x00000000
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg|grep kfbh.type
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg aun=11|grep kfbh.type
kfbh.type:                            8 ; 0x002: KFBTYP_CHNGDIR
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg blkn=254 aun=1|grep kfbh.type
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD

这里也比较明显,在aun 11的位置没有第一个au的备份
修改compatible.asm为12.2

[grid@localhost ~]$  asmcmd setattr -G XIFENFEI compatible.asm 12.2.0.0.0
[grid@localhost ~]$ asmcmd lsattr -l -G XIFENFEI
Name                        Value
access_control.enabled      FALSE
access_control.umask        066
appliance._partnering_type  NULL
au_size                     1048576
cell.smart_scan_capable     FALSE
cell.sparse_dg              allnonsparse
compatible.asm              12.2.0.0.0
compatible.rdbms            10.1.0.0.0
content.check               FALSE
content.type                data
disk_repair_time            3.6h
failgroup_repair_time       24.0h
idp.boundary                auto
idp.type                    dynamic
logical_sector_size         512
phys_meta_replicated        true
preferred_read.enabled      FALSE
scrub_async_limit           1
scrub_metadata.enabled      FALSE
sector_size                 512
thin_provisioned            FALSE

这里可以看到修改为compatible.asm=12.2之后，出现phys_meta_replicated属性

查看au的备份

[grid@localhost ~]$ for disk in `asmcmd lsdsk -G XIFENFEI --suppressheader`;
> do kfed read $disk | egrep "dskname|flags"; done
kfdhdb.dskname:           XIFENFEI_0000 ; 0x028: length=13
kfdhdb.flags:                         1 ; 0x0fc: 0x00000001
kfdhdb.dskname:           XIFENFEI_0001 ; 0x028: length=13
kfdhdb.flags:                         1 ; 0x0fc: 0x00000001
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg aun=11|grep kfbh.type
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg blkn=254 aun=1|grep kfbh.type
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg|grep kfbh.type
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD

这里就可以看到kfdhdb.flags为1，在au 11的地方也变为了磁盘头信息

模拟第一个au彻底损坏

[grid@localhost ~]$ dd if=/dev/zero of=/dev/xifenfei-sdg bs=1024k count=1 conv=notrunc
1+0 records in
1+0 records out
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg
kfbh.endian:                          0 ; 0x000: 0x00
kfbh.hard:                            0 ; 0x001: 0x00
kfbh.type:                            0 ; 0x002: KFBTYP_INVALID
kfbh.datfmt:                          0 ; 0x003: 0x00
kfbh.block.blk:                       0 ; 0x004: blk=0
kfbh.block.obj:                       0 ; 0x008: file=0
kfbh.check:                           0 ; 0x00c: 0x00000000
kfbh.fcn.base:                        0 ; 0x010: 0x00000000
kfbh.fcn.wrap:                        0 ; 0x014: 0x00000000
kfbh.spare1:                          0 ; 0x018: 0x00000000
kfbh.spare2:                          0 ; 0x01c: 0x00000000
000000000 00000000 00000000 00000000 00000000  [................]
  Repeat 255 times
KFED-00322: invalid content encountered during block traversal: [kfbtTraverseBlock][Invalid OSM block type][][0]

尝试mount磁盘组

SQL> alter diskgroup xifenfei mount;
alter diskgroup xifenfei mount
*
ERROR at line 1:
ORA-15032: not all alterations performed
ORA-15017: diskgroup "XIFENFEI" cannot be mounted
ORA-15040: diskgroup is incomplete

alert日志信息

SQL> alter diskgroup xifenfei mount
2017-04-22T08:30:00.889037-04:00
NOTE: cache registered group XIFENFEI 1/0xB15C368B
NOTE: cache began mount (first) of group XIFENFEI 1/0xB15C368B
NOTE: Assigning number (1,1) to disk (/dev/xifenfei-sdh)
2017-04-22T08:30:01.001544-04:00
ERROR: no read quorum in group: required 1, found 0 disks
2017-04-22T08:30:01.001737-04:00
NOTE: cache dismounting (clean) group 1/0xB15C368B (XIFENFEI)
NOTE: messaging CKPT to quiesce pins Unix process pid: 20894, image: oracle@localhost.localdomain (TNS V1-V3)
NOTE: dbwr not being msg'd to dismount
NOTE: LGWR not being messaged to dismount
NOTE: cache dismounted group 1/0xB15C368B (XIFENFEI)
NOTE: cache ending mount (fail) of group XIFENFEI number=1 incarn=0xb15c368b
NOTE: cache deleting context for group XIFENFEI 1/0xb15c368b
2017-04-22T08:30:01.028825-04:00
GMON dismounting group 1 at 2 for pid 23, osid 20894
2017-04-22T08:30:01.029146-04:00
NOTE: Disk XIFENFEI_0001 in mode 0x8 marked for de-assignment
ERROR: diskgroup XIFENFEI was not mounted
ORA-15032: not all alterations performed
ORA-15017: diskgroup "XIFENFEI" cannot be mounted
ORA-15040: diskgroup is incomplete
2017-04-22T08:30:01.036014-04:00
ERROR: alter diskgroup xifenfei mount

很明显由于xifenfei-sdg第一个au 已经被完全dd掉，xifenfei磁盘组无法mount，提示ORA-15040: diskgroup is incomplete

使用备份au还原

[grid@localhost ~]$ dd if=/dev/xifenfei-sdg skip=11 bs=1024k count=1 of=/tmp/sdg_header
1+0 records in
1+0 records out
1048576 bytes (1.0 MB) copied, 0.048576 s, 21.6 MB/s
[grid@localhost ~]$ kfed read /tmp/sdg_header |more
kfbh.endian:                          1 ; 0x000: 0x01
kfbh.hard:                          130 ; 0x001: 0x82
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD
kfbh.datfmt:                          2 ; 0x003: 0x02
kfbh.block.blk:                       0 ; 0x004: blk=0
kfbh.block.obj:              2147483648 ; 0x008: disk=0
kfbh.check:                  3085718230 ; 0x00c: 0xb7ec52d6
kfbh.fcn.base:                       41 ; 0x010: 0x00000029
kfbh.fcn.wrap:                        0 ; 0x014: 0x00000000
kfbh.spare1:                          0 ; 0x018: 0x00000000
kfbh.spare2:                          0 ; 0x01c: 0x00000000
kfdhdb.driver.provstr:         ORCLDISK ; 0x000: length=8
kfdhdb.driver.reserved[0]:            0 ; 0x008: 0x00000000
kfdhdb.driver.reserved[1]:            0 ; 0x00c: 0x00000000
kfdhdb.driver.reserved[2]:            0 ; 0x010: 0x00000000
kfdhdb.driver.reserved[3]:            0 ; 0x014: 0x00000000
kfdhdb.driver.reserved[4]:            0 ; 0x018: 0x00000000
kfdhdb.driver.reserved[5]:            0 ; 0x01c: 0x00000000
kfdhdb.compat:                203423744 ; 0x020: 0x0c200000
kfdhdb.dsknum:                        0 ; 0x024: 0x0000
kfdhdb.grptyp:                        1 ; 0x026: KFDGTP_EXTERNAL
kfdhdb.hdrsts:                        3 ; 0x027: KFDHDR_MEMBER
kfdhdb.dskname:           XIFENFEI_0000 ; 0x028: length=13
kfdhdb.grpname:                XIFENFEI ; 0x048: length=8
kfdhdb.fgname:            XIFENFEI_0000 ; 0x068: length=13
[grid@localhost ~]$ dd if=/tmp/sdg_header of=/dev/xifenfei-sdg bs=1024k count=1 conv=notrunc
1+0 records in
1+0 records out
1048576 bytes (1.0 MB) copied, 0.0262761 s, 39.9 MB/s
[grid@localhost ~]$ kfed read /dev/xifenfei-sdg|more
kfbh.endian:                          1 ; 0x000: 0x01
kfbh.hard:                          130 ; 0x001: 0x82
kfbh.type:                            1 ; 0x002: KFBTYP_DISKHEAD
kfbh.datfmt:                          2 ; 0x003: 0x02
kfbh.block.blk:                       0 ; 0x004: blk=0
kfbh.block.obj:              2147483648 ; 0x008: disk=0
kfbh.check:                  3085718230 ; 0x00c: 0xb7ec52d6
kfbh.fcn.base:                       41 ; 0x010: 0x00000029
kfbh.fcn.wrap:                        0 ; 0x014: 0x00000000
kfbh.spare1:                          0 ; 0x018: 0x00000000
kfbh.spare2:                          0 ; 0x01c: 0x00000000
kfdhdb.driver.provstr:         ORCLDISK ; 0x000: length=8
kfdhdb.driver.reserved[0]:            0 ; 0x008: 0x00000000
kfdhdb.driver.reserved[1]:            0 ; 0x00c: 0x00000000
kfdhdb.driver.reserved[2]:            0 ; 0x010: 0x00000000
kfdhdb.driver.reserved[3]:            0 ; 0x014: 0x00000000
kfdhdb.driver.reserved[4]:            0 ; 0x018: 0x00000000
kfdhdb.driver.reserved[5]:            0 ; 0x01c: 0x00000000
kfdhdb.compat:                203423744 ; 0x020: 0x0c200000
kfdhdb.dsknum:                        0 ; 0x024: 0x0000
kfdhdb.grptyp:                        1 ; 0x026: KFDGTP_EXTERNAL
kfdhdb.hdrsts:                        3 ; 0x027: KFDHDR_MEMBER
kfdhdb.dskname:           XIFENFEI_0000 ; 0x028: length=13
kfdhdb.grpname:                XIFENFEI ; 0x048: length=8
kfdhdb.fgname:            XIFENFEI_0000 ; 0x068: length=13

xifenfei磁盘组mount成功

[grid@localhost ~]$ sqlplus / as sysasm
SQL*Plus: Release 12.2.0.1.0 Production on Sat Apr 22 08:34:53 2017
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> alter diskgroup xifenfei mount;
Diskgroup altered.

asm alert日志

SQL> alter diskgroup xifenfei mount
2017-04-22T08:34:59.298838-04:00
NOTE: cache registered group XIFENFEI 1/0xFA6C368E
NOTE: cache began mount (first) of group XIFENFEI 1/0xFA6C368E
NOTE: Assigning number (1,0) to disk (/dev/xifenfei-sdg)
NOTE: Assigning number (1,1) to disk (/dev/xifenfei-sdh)
2017-04-22T08:35:05.447528-04:00
NOTE: GMON heartbeating for grp 1 (XIFENFEI)
GMON querying group 1 at 5 for pid 23, osid 21195
2017-04-22T08:35:05.449557-04:00
NOTE: cache is mounting group XIFENFEI created on 2017/04/22 08:13:39
NOTE: cache opening disk 0 of grp 1: XIFENFEI_0000 path:/dev/xifenfei-sdg
NOTE: 04/22/17 08:35:04 XIFENFEI.F1X0 found on disk 0 au 2 fcn 0.0 datfmt 2
NOTE: cache opening disk 1 of grp 1: XIFENFEI_0001 path:/dev/xifenfei-sdh
2017-04-22T08:35:05.450316-04:00
NOTE: cache mounting (first) external redundancy group 1/0xFA6C368E (XIFENFEI)
NOTE: cache recovered group 1 to fcn 0.352
NOTE: redo buffer size is 256 blocks (1056768 bytes)
2017-04-22T08:35:05.504356-04:00
NOTE: LGWR attempting to mount thread 1 for diskgroup 1 (XIFENFEI)
NOTE: LGWR found thread 1 closed at ABA 2.63 lock domain=0 inc#=0 instnum=1
NOTE: LGWR mounted thread 1 for diskgroup 1 (XIFENFEI)
2017-04-22T08:35:05.555647-04:00
NOTE: LGWR opened thread 1 (XIFENFEI) at fcn 0.352 ABA 3.64 lock domain=1 inc#=0 instnum=1
  gx.incarn=4201395854 mntstmp=2017/04/22 08:35:05.510000
2017-04-22T08:35:05.556006-04:00
NOTE: cache mounting group 1/0xFA6C368E (XIFENFEI) succeeded
NOTE: cache ending mount (success) of group XIFENFEI number=1 incarn=0xfa6c368e
2017-04-22T08:35:05.596616-04:00
NOTE: Instance updated compatible.asm to 12.2.0.0.0 for grp 1 (XIFENFEI).
2017-04-22T08:35:05.599181-04:00
NOTE: Instance updated compatible.rdbms to 10.1.0.0.0 for grp 1 (XIFENFEI).
2017-04-22T08:35:05.608332-04:00
SUCCESS: diskgroup XIFENFEI was mounted
2017-04-22T08:35:05.635588-04:00
SUCCESS: alter diskgroup xifenfei mount

ORA-28040: No matching authentication protocol

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：ORA-28040: No matching authentication protocol

电脑上面安装了三个版本的数据库10.2.0.3,11.2.0.1,12.1.0.2版本,使用他们分别尝试连接另外一个12.2.0.3的环境数据库发现只有12.1的版本客户端可以连接到12.2上面，其他版本报ORA-28040错误
分别测试连接，报ORA-28040错误

C:\Users\XIFENFEI>sqlplus sys/oracle@192.168.137.121/orcl12c2 as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on 星期三 7月 20 00:03:01 2016
Copyright (c) 1982, 2014, Oracle.  All rights reserved.
连接到:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL>
SQL>
C:\Users\XIFENFEI>D:\app\FAL\product\11.2.0\dbhome_1\bin\sqlplus sys/oracle@192.168.137.121/orcl12c2 as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on 星期三 7月 20 00:10:33 2016
Copyright (c) 1982, 2010, Oracle.  All rights reserved.
ERROR:
ORA-28040: No matching authentication protocol
C:\Users\XIFENFEI>D:\app\product\10.2.0\db_1\bin\sqlplus sys/oracle@192.168.137.121/orcl12c2 as sysdba
SQL*Plus: Release 10.2.0.3.0 - Production on 星期三 7月 20 00:09:30 2016
Copyright (c) 1982, 2006, Oracle.  All Rights Reserved.
ERROR:
ORA-28040: 没有匹配的验证协议
请输入用户名:

ORA-28040错误说明

28040, 0000, "No matching authentication protocol"
// *Cause:  There was no acceptable authentication protocol for
//          either client or server.
// *Action: The administrator should set the values of the
//          SQLNET.ALLOWED_LOGON_VERSION_SERVER and
//          SQLNET.ALLOWED_LOGON_VERSION_CLIENT parameters, on both the
//          client and on the server, to values that match the minimum
//          version software supported in the system.
//          This error is also raised when the client is authenticating to
//          a user account which was created without a verifier suitable for
//          the client software version. In this situation, that account's
//          password must be reset, in order for the required verifier to
//          be generated and allow authentication to proceed successfully.

解决方法
在服务端的sqlnet.ora文件中加入上如下信息，然后重启监听

[oracle@ora1221 admin]$ vi sqlnet.ora
SQLNET.ALLOWED_LOGON_VERSION_CLIENT=8
SQLNET.ALLOWED_LOGON_VERSION_SERVER=8
[oracle@ora1221 admin]$ lsnrctl stop
LSNRCTL for Linux: Version 12.2.0.0.3 - Production on 17-JUN-2016 06:36:13
Copyright (c) 1991, 2016, Oracle.  All rights reserved.
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
The command completed successfully
[oracle@ora1221 admin]$ lsnrctl start
LSNRCTL for Linux: Version 12.2.0.0.3 - Production on 17-JUN-2016 06:36:17
Copyright (c) 1991, 2016, Oracle.  All rights reserved.
Starting /u01/app/oracle/product/12.2.0/db_2/bin/tnslsnr: please wait...
TNSLSNR for Linux: Version 12.2.0.0.3 - Production
Log messages written to /u01/app/oracle/diag/tnslsnr/ora1221/listener/alert/log.xml
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=ora1221)(PORT=1521)))
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias                     LISTENER
Version                   TNSLSNR for Linux: Version 12.2.0.0.3 - Production
Start Date                17-JUN-2016 06:36:17
Uptime                    0 days 0 hr. 0 min. 0 sec
Trace Level               off
Security                  ON: Local OS Authentication
SNMP                      OFF
Listener Log File         /u01/app/oracle/diag/tnslsnr/ora1221/listener/alert/log.xml
Listening Endpoints Summary...
  (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=ora1221)(PORT=1521)))
The listener supports no services
The command completed successfully

sqlnet中参数说明
SQLNET.ALLOWED_LOGON_VERSION_SERVER 是服务端参数对于jdbc和oci都生效,该参数不是只具体数据库版本,而是指授权协议的版本
SQLNET.ALLOWED_LOGON_VERSION_CLIENT 是指作为客户端连接其他实例的时候生效,也是只授权协议版本,而且该参数只对oci生效,jdbc 需要通过在代码中类似实现

OracleDataSource ods = new OracleDataSource();
ods.setURL(jdbcURL);
ods.setUser("scott");
ods.setPassword("tiger");
Properties props = new Properties();
props.put("oracle.jdbc.allowedLogonVersion", 12);
ods.setConnectionProperties(props);
Connection con = ods.getConnection();

上述两个参数可以填写值
12a for Oracle Database 12c release 12.1.0.2 or later authentication protocols (strongest protection)
12 for the critical patch updates CPUOct2012 and later Oracle Database 11g authentication protocols (recommended)
11 for Oracle Database 11g authentication protocols (default)
10 for Oracle Database 10g authentication protocols
9 for Oracle9i Database authentication protocol
8 for Oracle8i Database authentication protocol
allowed_logon_version_server

具体描述请见:http://docs.oracle.com/database/121/NETRF/sqlnet.htm#NETRF2010

再次测试连接

C:\Users\XIFENFEI>D:\app\FAL\product\11.2.0\dbhome_1\bin\sqlplus sys/oracle@192.168.137.121/orcl12c2 as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on 星期三 7月 20 00:20:21 2016
Copyright (c) 1982, 2010, Oracle.  All rights reserved.
连接到:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL> exit
从 Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production 断开
C:\Users\XIFENFEI>D:\app\product\10.2.0\db_1\bin\sqlplus sys/oracle@192.168.137.121/orcl12c2 as sysdba
SQL*Plus: Release 10.2.0.3.0 - Production on 星期三 7月 20 00:20:28 2016
Copyright (c) 1982, 2006, Oracle.  All Rights Reserved.
连接到:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL>
C:\Users\XIFENFEI>sqlplus sys/oracle@192.168.137.121/orcl12c2 as sysdba
SQL*Plus: Release 12.1.0.2.0 Production on 星期三 7月 20 00:20:55 2016
Copyright (c) 1982, 2014, Oracle.  All rights reserved.
连接到:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production

该问题在jdbc中也表现明显，建议参考Starting With Oracle JDBC Drivers (文档 ID 401934.1)和Client / Server Interoperability Support Matrix for Different Oracle Versions (文档 ID 207303.1)选择完全兼容性的客户端和jdbc版本,另外可以关注相关文章:
ORA-28040 and SQLNET.ALLOWED_LOGON_VERSION_CLIENT for JDBC Thin Clients (文档 ID 2000339.1)
ORA-28040 Using JDBC Connection to 12c Database (文档 ID 2111118.1)
JDBC Version 10.2.0.4 Produces ORA-28040 Connecting To Oracle 12c (12.1.0.2) Database (文档 ID 2023160.1)
ORA-28040 and SQLNET.ALLOWED_LOGON_VERSION_CLIENT for JDBC Thin Clients (文档 ID 2000339.1)

Oracle 12c undo异常处理—root pdb undo异常

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：Oracle 12c undo异常处理—root pdb undo异常

在12c pdb环境中如果root pdb的undo文件异常，数据库该如何恢复呢？这篇文章模拟undo丢失的情况下进行恢复
模拟环境
三个会话，其中第一个会话对pdb1中的表进行操作，并且有事务未提交,第二个会话对pdb2进行操作，也未提交事务；第三个会话直接abort库，模拟突然库异常，然后删除root pdb下面的undo文件

--会话1
[oracle@ora1221 oradata]$ sqlplus  / as sysdba
SQL*Plus: Release 12.2.0.0.3 Production on Thu Jun 16 22:24:20 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
Database opened.
SQL>
SQL>
SQL>
SQL> show pdbs;
    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           MOUNTED
         4 PDB2                           MOUNTED
SQL> alter session set container=pdb1;
Session altered.
SQL> alter database open;
Database altered.
SQL>  create user chf identified by oracle;
User created.
SQL> grant dba to chf;
Grant succeeded.
SQL> create table chf.t_xifenfei_p1 as
  2  select * from dba_objects;
Table created.
SQL> insert into chf.t_xifenfei_p1
  2  select * from dba_objects;
72427 rows created.
SQL> select count(*) from chf.t_xifenfei_p1;
  COUNT(*)
----------
    144853
--会话2
[oracle@ora1221 ~]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Thu Jun 16 22:34:01 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL> alter session set container=pdb2;
Session altered.
SQL> alter database open;
Database altered.
SQL>  create user chf identified by oracle;
User created.
SQL> grant dba to chf;
Grant succeeded.
SQL>  create table chf.t_xifenfei_p2
  2  as select * from dba_objects;
Table created.
SQL> delete from chf.t_xifenfei_p2;
72426 rows deleted.
SQL> select count(*) from chf.t_xifenfei_p2;
  COUNT(*)
----------
    0
--会话3
[oracle@ora1221 ~]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Thu Jun 16 22:36:16 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL> shutdown abort
ORACLE instance shut down.
--删除cdb undo文件
[oracle@ora1221 orcl12c2]$ ls -ltr
total 2040912
drwxr-x---. 2 oracle oinstall      4096 Jun 16 18:26 pdbseed
drwxr-x---. 2 oracle oinstall      4096 Jun 16 18:27 pdb2
drwxr-x---. 2 oracle oinstall      4096 Jun 16 18:28 pdb1
-rw-r-----. 1 oracle oinstall 209715712 Jun 16 22:24 redo03.log
-rw-r-----. 1 oracle oinstall   5251072 Jun 16 22:24 users01.dbf
-rw-r-----. 1 oracle oinstall  34611200 Jun 16 22:25 temp01.dbf
-rw-r-----. 1 oracle oinstall 849354752 Jun 16 22:35 system01.dbf
-rw-r-----. 1 oracle oinstall  73408512 Jun 16 22:35 undotbs01.dbf
-rw-r-----. 1 oracle oinstall 492838912 Jun 16 22:35 sysaux01.dbf
-rw-r-----. 1 oracle oinstall 209715712 Jun 16 22:36 redo02.log
-rw-r-----. 1 oracle oinstall 209715712 Jun 16 22:36 redo01.log
-rw-r-----. 1 oracle oinstall  18726912 Jun 16 22:36 control02.ctl
-rw-r-----. 1 oracle oinstall  18726912 Jun 16 22:36 control01.ctl
[oracle@ora1221 orcl12c2]$ rm undotbs01.dbf
[oracle@ora1221 orcl12c2]$ ls -l un*
ls: cannot access un*: No such file or directory

启动数据库
由于有undo文件丢失数据库在启动的时候检测到文件丢失(ORA-01157)，无法open,offline文件后依旧无法启动(ORA-00376)

[oracle@ora1221 orcl12c2]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Thu Jun 16 22:51:21 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to an idle instance.
SQL> startup pfile='/tmp/pfile'
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
ORA-01157: cannot identify/lock data file 4 - see DBWR trace file
ORA-01110: data file 4: '/u01/app/oracle/oradata/orcl12c2/undotbs01.dbf'
offline 数据文件
SQL> alter database datafile 4 offline ;
alter database datafile 4 offline
*
ERROR at line 1:
ORA-01145: offline immediate disallowed unless media recovery enabled
SQL>  alter database datafile 4 offline drop;
Database altered.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00603: ORACLE server session terminated by fatal error
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-00604: error occurred at recursive SQL level 1
ORA-00376: file 4 cannot be read at this time
ORA-01110: data file 4: '/u01/app/oracle/oradata/orcl12c2/undotbs01.dbf'
Process ID: 7547
Session ID: 16 Serial number: 56234

把undo_management修改为manual后启动库，依旧报ORA-00376

SQL> startup pfile='/tmp/pfile' mount;
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
SQL> show parameter undo_management;
NAME                                 TYPE
------------------------------------ ----------------------
VALUE
------------------------------
undo_management                      string
MANUAL
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00603: ORACLE server session terminated by fatal error
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-00604: error occurred at recursive SQL level 1
ORA-00376: file 4 cannot be read at this time
ORA-01110: data file 4: '/u01/app/oracle/oradata/orcl12c2/undotbs01.dbf'
Process ID: 7981
Session ID: 16 Serial number: 56572

设置_corrupted_rollback_segments参数

SQL> startup pfile='/tmp/pfile' mount;
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
SQL> show parameter _corrupted_rollback_segments;
NAME                                 TYPE
------------------------------------ ----------------------
VALUE
------------------------------
_corrupted_rollback_segments         string
_SYSSMU1_3200770482$, _SYSSMU2
_3597554035$, _SYSSMU3_2898427
493$, _SYSSMU4_670955920$, _SY
SSMU5_1233449977$, _SYSSMU6_32
67641983$, _SYSSMU7_2822479342
$, _SYSSMU8_1645196706$, _SYSS
MU9_3032014485$, _SYSSMU10_474
465626$
SQL> alter database open;
Database altered.

通过设置_corrupted_rollback_segments参数之后，数据库正常启动，下面继续其他pdb

open pdb1

SQL> alter session set container=pdb1;
Session altered.
SQL> alter database open;
Database altered.
SQL> select count(*) from chf.t_xifenfei_p1;
  COUNT(*)
----------
     72426

pdb2 open

SQL> alter session set container=pdb2;
Session altered.
SQL> alter database open;
Database altered.
SQL> select count(*) from chf.t_xifenfei_p2;
  COUNT(*)
----------
     72426

至此数据库基本上恢复完成，但是看到的pdb里面两个测试表的数据和我们预测的有一定的偏差,看来cdb中的undo和pdb中的undo还是有一定的依赖关系.同时也说明了root的undo异常对于其他pdb的open最少在恢复上面影响不大.下一篇测试业务pdb中undo异常处理

Oracle 12c redo 丢失恢复

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：Oracle 12c redo 丢失恢复

模拟redo丢失
对数据库的一个pdb模拟事务操作，然后abort库，并且删除所有redo，模拟生产环境redo丢失的case

[oracle@ora1221 oradata]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Wed Jun 15 10:13:20 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
Database opened.
SQL>
SQL>
SQL> set pages 100
SQL> show pdbs;
    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           MOUNTED
         4 PDB2                           MOUNTED
SQL> select con_id,file#,checkpoint_change# from v$datafile_header order by 1;
    CON_ID      FILE# CHECKPOINT_CHANGE#
---------- ---------- ------------------
         1          1            1500157
         1          3            1500157
         1          4            1500157
         1          7            1500157
         2          5            1371280
         2          6            1371280
         2          8            1371280
         3          9            1499902
         3         12            1499902
         3         11            1499902
         3         10            1499902
         4         15            1499903
         4         14            1499903
         4         13            1499903
         4         16            1499903
15 rows selected.
SQL> alter PLUGGABLE database pdb1 open;
Pluggable database altered.
SQL> show pdbs;
    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           READ WRITE NO
         4 PDB2                           MOUNTED
SQL> alter session set container=pdb1;
Session altered.
SQL> create user chf identified by oracle;
User created.
SQL> grant dba to chf;
Grant succeeded.
SQL> create table chf.t_pdb1_xifenfei as select * from dba_objects;
Table created.
SQL> delete from chf.t_pdb1_xifenfei;
72426 rows deleted.
--另外一个节点
[oracle@ora1221 ~]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Wed Jun 15 10:19:21 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL> shutdown abort
ORACLE instance shut down.
[oracle@ora1221 orcl12c2]$ ls redo*
redo01.log  redo02.log  redo03.log
[oracle@ora1221 orcl12c2]$ rm redo0*
[oracle@ora1221 orcl12c2]$ ls -l redo*
ls: cannot access redo*: No such file or directory

尝试启动数据库

[oracle@ora1221 orcl12c2]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Wed Jun 15 10:26:20 2016
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to an idle instance.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-00313: open failed for members of log group 1 of thread 1
ORA-00312: online log 1 thread 1: '/u01/app/oracle/oradata/orcl12c2/redo01.log'
ORA-27037: unable to obtain file status
Linux-x86_64 Error: 2: No such file or directory
Additional information: 7

使用隐含参数启动

----pfile里面增加
_allow_error_simulation=TRUE
_allow_resetlogs_corruption=true
~
SQL> shutdown immediate;
ORA-01109: database not open
Database dismounted.
ORACLE instance shut down
SQL> startup pfile='/tmp/pfile' mount
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-00603: ORACLE server session terminated by fatal error
ORA-01092: ORACLE instance terminated. Disconnection forced
ORA-00600: internal error code, arguments: [kcbzib_kcrsds_1], [], [], [], [],
[], [], [], [], [], [], []
Process ID: 36797
Session ID: 16 Serial number: 24277

继续重启库
ORA-600 kcbzib_kcrsds_1错误尝试重启数据库,如果不行,考虑使用bbed修改文件头信息

SQL> startup mount pfile='/tmp/pfile'
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
SQL> recover database until cancel;
ORA-00283: recovery session canceled due to errors
ORA-16433: The database or pluggable database must be opened in read/write
mode.
SQL> alter database backup controlfile to trace as '/tmp/ctl';
alter database backup controlfile to trace as '/tmp/ctl'
*
ERROR at line 1:
ORA-16433: The database or pluggable database must be opened in read/write
mode.

重建控制文件

SQL> startup nomount pfile='/tmp/pfile'
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
SQL> CREATE CONTROLFILE REUSE DATABASE "orcl12c2" RESETLOGS  NOARCHIVELOG
  2      MAXLOGFILES 50
  3      MAXLOGMEMBERS 5
  4      MAXDATAFILES 100
  5      MAXINSTANCES 1
  6      MAXLOGHISTORY 226
  7  LOGFILE
  8    GROUP 1 '/u01/app/oracle/oradata/orcl12c2/redo01.log'  SIZE 200M,
  9    GROUP 2 '/u01/app/oracle/oradata/orcl12c2/redo02.log'  SIZE 200M,
 10    GROUP 3 '/u01/app/oracle/oradata/orcl12c2/redo03.log'  SIZE 200M
 11  DATAFILE
 12  '/u01/app/oracle/oradata/orcl12c2/system01.dbf',
 13  '/u01/app/oracle/oradata/orcl12c2/sysaux01.dbf',
 14  '/u01/app/oracle/oradata/orcl12c2/undotbs01.dbf',
 15  '/u01/app/oracle/oradata/orcl12c2/pdbseed/system01.dbf',
 16  '/u01/app/oracle/oradata/orcl12c2/pdbseed/sysaux01.dbf',
 17  '/u01/app/oracle/oradata/orcl12c2/users01.dbf',
 18  '/u01/app/oracle/oradata/orcl12c2/pdbseed/undotbs01.dbf',
 19  '/u01/app/oracle/oradata/orcl12c2/pdb1/system01.dbf',
 20  '/u01/app/oracle/oradata/orcl12c2/pdb1/sysaux01.dbf',
 21  '/u01/app/oracle/oradata/orcl12c2/pdb1/undotbs01.dbf',
 22  '/u01/app/oracle/oradata/orcl12c2/pdb1/users01.dbf',
 23  '/u01/app/oracle/oradata/orcl12c2/pdb2/system01.dbf',
 24  '/u01/app/oracle/oradata/orcl12c2/pdb2/sysaux01.dbf',
 25  '/u01/app/oracle/oradata/orcl12c2/pdb2/undotbs01.dbf',
 26  '/u01/app/oracle/oradata/orcl12c2/pdb2/users01.dbf'
 27  CHARACTER SET AL32UTF8
 28  ;
Control file created.
SQL> recover database until cancel;
ORA-00283: recovery session canceled due to errors
ORA-01610: recovery using the BACKUP CONTROLFILE option must be done
SQL> recover database until cancel using backup controlfile;
ORA-00279: change 1500161 generated at 06/15/2016 10:40:42 needed for thread 1
ORA-00289: suggestion :
/u01/app/oracle/product/12.2.0/db_2/dbs/arch1_1_914582438.dbf
ORA-00280: change 1500161 for thread 1 is in sequence #1
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
/u01/app/oracle/oradata/orcl12c2/redo01.log
Log applied.
Media recovery complete.
SQL> alter database open resetlogs;
Database altered.

<strong>open过程alert日志</strong>

<strong>open pdb1</strong>

SQL> alter PLUGGABLE database pdb1  open;
Pluggable database altered.

pdb1 open alert日志

2016-06-15T11:13:39.423057+08:00
alter PLUGGABLE database pdb1  open
PDB1(3):Autotune of undo retention is turned on.
2016-06-15T11:13:39.495559+08:00
PDB1(3):Endian type of dictionary set to little
PDB1(3):[40547] Successfully onlined Undo Tablespace 2.
PDB1(3):Undo initialization finished serial:0 start:371149831 end:371149872 diff:41 ms (0.0 seconds)
PDB1(3):Database Characterset for PDB1 is AL32UTF8
PDB1(3):*********************************************************************
PDB1(3):WARNING: The following temporary tablespaces in container(PDB1)
PDB1(3):         contain no files.
PDB1(3):         This condition can occur when a backup controlfile has
PDB1(3):         been restored.  It may be necessary to add files to these
PDB1(3):         tablespaces.  That can be done using the SQL statement:
PDB1(3):
PDB1(3):         ALTER TABLESPACE <tablespace_name> ADD TEMPFILE
PDB1(3):
PDB1(3):         Alternatively, if these temporary tablespaces are no longer
PDB1(3):         needed, then they can be dropped.
PDB1(3):           Empty temporary tablespace: TEMP
PDB1(3):*********************************************************************
PDB1(3):Opatch validation is skipped for PDB PDB1 (con_id=0)
PDB1(3):Opening pdb with no Resource Manager plan active
Pluggable database PDB1 opened read write
Completed: alter PLUGGABLE database pdb1  open

open pdb2

SQL> alter PLUGGABLE database pdb2 open;
alter PLUGGABLE database pdb2 open
*
ERROR at line 1:
ORA-00600: internal error code, arguments: [17090], [], [], [], [], [], [], [],
[], [], [], []

分析alert日志和trace文件

--alert日志部分
PDB1(3):alter PLUGGABLE database pdb2 open
PDB1(3):ORA-65118 signalled during: alter PLUGGABLE database pdb2 open...
2016-06-15T11:28:57.439963+08:00
PDB1(3):Unified Audit: Audit record write to table failed due to ORA-25153.
Writing the audit record to OS spillover file. Please grep in the trace files for ORA-25153 for more diagnostic information.
Errors in file /u01/app/oracle/diag/rdbms/orcl12c2/orcl12c2/trace/orcl12c2_ora_40547.trc  (incident=29073) (PDBNAME=PDB1):
ORA-00600: internal error code, arguments: [17090], [], [], [], [], [], [], [], [], [], [], []
PDB1(3):Incident details in: /u01/app/oracle/diag/rdbms/orcl12c2/orcl12c2/incident/incdir_29073/orcl12c2_ora_40547_i29073.trc
PDB1(3):*****************************************************************
PDB1(3):An internal routine has requested a dump of selected redo.
PDB1(3):This usually happens following a specific internal error, when
PDB1(3):analysis of the redo logs will help Oracle Support with the
PDB1(3):diagnosis.
PDB1(3):It is recommended that you retain all the redo logs generated (by
PDB1(3):all the instances) during the past 12 hours, in case additional
PDB1(3):redo dumps are required to help with the diagnosis.
PDB1(3):*****************************************************************
2016-06-15T11:28:59.123041+08:00
PDB1(3):Use ADRCI or Support Workbench to package the incident.
See Note 411.1 at My Oracle Support for error and packaging details.
2016-06-15T11:28:59.945667+08:00
Dumping diagnostic data in directory=[cdmp_20160615112859], requested by (instance=1, osid=40547), summary=[incident=29073].
2016-06-15T11:35:59.987419+08:00
PDB1(3): alter PLUGGABLE database pdb2 open
PDB1(3):ORA-65118 signalled during:  alter PLUGGABLE database pdb2 open...
--trace部分
PARSING IN CURSOR #0x7f051a3d7650 len=118 dep=1 uid=0 oct=3 lid=0 tim=372490287736 hv=1128335472 ad='0x6ca82f00' sqlid='gu930gd1n223h'
select tablespace_name, tablespace_size, allocated_space, free_space, con_id  from cdb_temp_free_space order by con_id
END OF STMT
EXEC #0x7f051a3d7650:c=0,e=144,p=0,cr=0,cu=0,mis=0,r=0,dep=1,og=4,plh=2538033465,tim=372490287732
FETCH #0x7f051a3d7650:c=0,e=290,p=0,cr=14,cu=0,mis=0,r=0,dep=1,og=4,plh=2538033465,tim=372490288109
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 52 FileOperation=2 fileno=0 filetype=36 obj#=402 tim=372490288373
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 17 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490288577
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 3 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490288655
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 690 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490289365
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 6 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490289470
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 445 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490289934
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 3 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490289983
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 375 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490290374
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 6 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490290453
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 367 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490290839
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 3 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490290882
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 355 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490291252
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 4 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490291298
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 276 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490291590
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 1 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490291614
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 256 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490291879
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 2 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490291903
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 261 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490292172
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 30 FileOperation=3 fileno=0 filetype=36 obj#=402 tim=372490292225
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 934 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490293171
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 3 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490293208
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 245 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490293465
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 262 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490293755
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 1 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490293780
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 250 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490294039
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 256 FileOperation=8 fileno=1 filetype=36 obj#=402 tim=372490294323
WAIT #0x7f051bd5f870: nam='Disk file operations I/O' ela= 8 FileOperation=5 fileno=0 filetype=36 obj#=402 tim=372490294359
2016-06-15T11:36:00.055196+08:00
Incident 29074 created, dump file: /u01/app/oracle/diag/rdbms/orcl12c2/orcl12c2/incident/incdir_29074/orcl12c2_ora_40547_i29074.trc
ORA-00600: internal error code, arguments: [17090], [], [], [], [], [], [], [], [], [], [], []

从中可以判断出来是由于CDB$ROOT的未增加tempfile导致

SQL> alter tablespace temp add tempfile '/u01/app/oracle/oradata/orcl12c2/temp01.dbf' reuse;
Tablespace altered.
SQL>  alter PLUGGABLE database pdb2 open;
Pluggable database altered.

查看数据库恢复情况

SQL> show pdbs;
    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 PDB1                           READ WRITE NO
         4 PDB2                           READ WRITE NO
SQL> select con_id,file#,checkpoint_change#,resetlogs_change# from v$datafile_header;
    CON_ID      FILE# CHECKPOINT_CHANGE# RESETLOGS_CHANGE#
---------- ---------- ------------------ -----------------
         1          1            2500167           1500164
         1          3            2500167           1500164
         1          4            2500167           1500164
         2          5            1371280           1341067
         2          6            1371280           1341067
         1          7            2500167           1500164
         2          8            1371280           1341067
         3          9            2501017           1500164
         3         10            2501017           1500164
         3         11            2501017           1500164
         3         12            2501017           1500164
         4         13            2502748           1500164
         4         14            2502748           1500164
         4         15            2502748           1500164
         4         16            2502748           1500164
15 rows selected.

至此基本上测试完成在在cdb环境中丢失redo的恢复。在生产中，需要把temp加全，并且建议重建数据库

Resize operation completed for file#

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：Resize operation completed for file#

Orale 12c DataGuard环境中备库出现Resize operation completed for file# 现象
数据库版本

[oracle@ray01 ~]$ opatch lspatches
22291127;Database Patch Set Update : 12.1.0.2.160419 (22291127)
OPatch succeeded.
SQL> select * from v$version;
BANNER                                                                               CON_ID
-------------------------------------------------------------------------------- ----------
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production              0
PL/SQL Release 12.1.0.2.0 - Production                                                    0
CORE    12.1.0.2.0      Production                                                        0
TNS for Linux: Version 12.1.0.2.0 - Production                                            0
NLSRTL Version 12.1.0.2.0 - Production                                                    0

alert日志提示

Mon Jun 27 20:56:37 2016
Resize operation completed for file# 18, old size 25600000K, new size 30720000K
Mon Jun 27 20:56:56 2016
Archived Log entry 210 added for thread 1 sequence 286 rlc 915405135 ID 0x2316988c dest 2:
Mon Jun 27 20:57:01 2016
Primary database is in MAXIMUM PERFORMANCE mode
RFS[211]: Assigned to RFS process (PID:22867)
RFS[211]: Selected log 11 for thread 1 sequence 287 dbid 588725388 branch 915405135
Mon Jun 27 20:57:14 2016
Resize operation completed for file# 17, old size 25600000K, new size 30720000K
Mon Jun 27 07:57:15 2016
Archived Log entry 211 added for thread 1 sequence 287 ID 0x2316988c dest 1:
Mon Jun 27 20:57:15 2016
Resize operation completed for file# 3, old size 972800K, new size 983040K
Mon Jun 27 20:57:15 2016
Primary database is in MAXIMUM PERFORMANCE mode
RFS[212]: Assigned to RFS process (PID:22873)
RFS[212]: Selected log 11 for thread 1 sequence 288 dbid 588725388 branch 915405135
Mon Jun 27 20:57:15 2016
Resize operation completed for file# 3, old size 983040K, new size 1024000K
Resize operation completed for file# 3, old size 1024000K, new size 1034240K
Mon Jun 27 20:57:54 2016
Resize operation completed for file# 15, old size 25600000K, new size 30720000K
Mon Jun 27 20:58:15 2016
Resize operation completed for file# 18, old size 30720000K, new size 33554416K
Mon Jun 27 20:58:34 2016
Resize operation completed for file# 17, old size 30720000K, new size 33554416K
Mon Jun 27 20:58:54 2016
Resize operation completed for file# 15, old size 30720000K, new size 33554416K

大量Resize operation completed for file# 操作记录,给人感觉比较烦,根据多年使用oracle的经验,这种现象很可能有隐含参数或者event屏蔽,隐含参数可以猜测到,event需要查询官方资料.

查询汗resize的隐含参数

SQL> col name for a52
SQL> col value for a24
SQL> col description for a50
set linesize 150
select a.ksppinm name,b.ksppstvl value,a.ksppdesc description
  from x$ksppi a,x$ksppcv b
 where a.inst_id = USERENV ('Instance')
   and b.inst_id = USERENV ('Instance')
   and a.indx = b.indx
SQL> SQL>   2    3    4    5    6     and upper(a.ksppinm) LIKE upper('%&param%')
  7  order by name
/
  8  Enter value for param: resize
old   6:    and upper(a.ksppinm) LIKE upper('%&param%')
new   6:    and upper(a.ksppinm) LIKE upper('%resize%')
NAME                                                 VALUE                    DESCRIPTION
---------------------------------------------------- ------------------------ --------------------------------------------------
_asm_skip_resize_check                               FALSE                    skip the checking of the clients for s/w compatibi
                                                                              lity for resize
_bct_public_dba_buffer_dynresize                     2                        allow dynamic resizing of public dba buffers, zero
                                                                               to disable
_disable_file_resize_logging                         FALSE                    disable file resize logging to alert log

从这里可以发现_disable_file_resize_logging参数默认值为false,表示显示文件resize的提示,设置为true应该就可以解决该问题.

_use_single_log_writer和_max_outstanding_log_writes

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：_use_single_log_writer和_max_outstanding_log_writes

SCALABLE LGWR是12cR1中引入的一个令人激动的特性，这是由于在OLTP环境中LGWR写日志往往成为系统的主要性能瓶颈，如果LGWR进程能像DBWR(DBW0~DBWn)那样多进程（LGNN）写出redo到LOGFILE那么就可能大幅释放OLTP的并发能力，增长Transcation系统的单位时间事务处理能力。这里在12.2版本中进行测试，确定_use_single_log_writer和_max_outstanding_log_writes参数对于SCALABLE LGWR特性的影响
数据库版本

SQL> select * from v$version;
BANNER                                                                                         CON_ID
------------------------------------------------------------------------------------------ ----------
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production                        0
PL/SQL Release 12.2.0.0.3 - Production                                                              0
CORE    12.2.0.0.3      Production                                                                  0
TNS for Linux: Version 12.2.0.0.3 - Production                                                      0
NLSRTL Version 12.2.0.0.3 - Production                                                              0

_use_single_log_writer和_max_outstanding_log_writes默认值

SQL> /
Enter value for param: _use_single_log_writer
old   6:    and upper(a.ksppinm) LIKE upper('%&param%')
new   6:    and upper(a.ksppinm) LIKE upper('%_use_single_log_writer%')
NAME                                                 VALUE                    DESCRIPTION
---------------------------------------------------- ------------------------ -------------------------------------------
_use_single_log_writer                               ADAPTIVE                 Use a single process for redo log writing
SQL> /
Enter value for param: _max_outstanding_log_writes
old   6:    and upper(a.ksppinm) LIKE upper('%&param%')
new   6:    and upper(a.ksppinm) LIKE upper('%_max_outstanding_log_writes%')
NAME                                                 VALUE                    DESCRIPTION
---------------------------------------------------- ------------------------ ----------------------------------------------
_max_outstanding_log_writes                          2                        Maximum number of outstanding redo log writes

lg进程数量
这里可以看出来，有一个lgwr进程，两个lg进程和_max_outstanding_log_writes参数配置匹配

[oracle@ora1221 ~]$ ps -ef|grep ora_lg
oracle    49790      1  0 10:32 ?        00:00:00 ora_lgwr_orcl12c2
oracle    49794      1  0 10:32 ?        00:00:00 ora_lg00_orcl12c2
oracle    49798      1  0 10:32 ?        00:00:00 ora_lg01_orcl12c2

修改_max_outstanding_log_writes参数
通过修改_max_outstanding_log_writes参数为4，发现lg进程数量也变为了4，证明_max_outstanding_log_writes进程决定lg进程数量

SQL> alter system set "_max_outstanding_log_writes"=4 ;
alter system set "_max_outstanding_log_writes"=4
                 *
ERROR at line 1:
ORA-02095: specified initialization parameter cannot be modified
SQL> alter system set "_max_outstanding_log_writes"=4 scope=spfile;
System altered.
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
Database opened.
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
[oracle@ora1221 ~]$ ps -ef|grep lg
oracle    72339      1  0 13:45 ?        00:00:00 ora_lgwr_orcl12c2
oracle    72343      1  0 13:45 ?        00:00:00 ora_lg00_orcl12c2
oracle    72347      1  0 13:45 ?        00:00:00 ora_lg01_orcl12c2
oracle    72351      1  0 13:45 ?        00:00:00 ora_lg02_orcl12c2
oracle    72359      1  0 13:45 ?        00:00:00 ora_lg03_orcl12c2

修改_use_single_log_writer参数
通过测试_use_single_log_writer参数修改，我们可以确定_use_single_log_writer修改为true后，数据库恢复到12c之前的lgwr管理方式

[oracle@ora1221 ~]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Thu Aug 6 13:45:33 2015
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to:
Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
SQL> alter system set "_use_single_log_writer"=1 ;
alter system set "_use_single_log_writer"=1
                 *
ERROR at line 1:
ORA-02095: specified initialization parameter cannot be modified
SQL>  alter system set "_use_single_log_writer"=1 scope=spfile;
 alter system set "_use_single_log_writer"=1 scope=spfile
*
ERROR at line 1:
ORA-00096: invalid value 1 for parameter _use_single_log_writer, must be from
among ADAPTIVE, FALSE, TRUE
SQL> alter system set "_use_single_log_writer"=TRUE scope=spfile;
System altered.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
[oracle@ora1221 ~]$ ps -ef|grep lg
oracle    72702  71510  0 13:46 pts/0    00:00:00 grep lg
[oracle@ora1221 ~]$ ss
SQL*Plus: Release 12.2.0.0.3 Production on Thu Aug 6 13:46:50 2015
Copyright (c) 1982, 2016, Oracle.  All rights reserved.
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  8260048 bytes
Variable Size             671090224 bytes
Database Buffers         1828716544 bytes
Redo Buffers                8515584 bytes
Database mounted.
Database opened.
SQL> exit
Disconnected from Oracle Database 12c Enterprise Edition Release 12.2.0.0.3 - 64bit Production
[oracle@ora1221 ~]$ ps -ef|grep lg
oracle    72754      1  0 13:46 ?        00:00:00 ora_lgwr_orcl12c2
oracle    73008  71510  0 13:47 pts/0    00:00:00 grep lg

从这里可以确定_use_single_log_writer确定是否启用SCALABLE LGWR(多个lg子进程),_max_outstanding_log_writes确定lg进程个数

Oracle 12C Active Data Guard Far Sync 配置

联系：手机/微信(+86 17813235971) QQ(107644445)

标题：Oracle 12C Active Data Guard Far Sync 配置

Active Data Guard Far Sync是Oracle 12c的新功能（也称为Far Sync Standby），Far Sync功能的实现是通过在距离主库(Primary Database)相对较近的地点配置Far Sync实例，主库(Primary Database) 同步(synchronous)传输redo到Far Sync实例，然后Far Sync实例再将redo异步(asynchronous)传输到终端备库(Standby Database)。这样既可以保证零数据丢失又可以降低主库压力。Far Sync实例只有密码文件，init参数文件和控制文件，而没有数据文件。如果redo 传输采用Maximum Availability模式，我们可以在距离生产中心(Primary Database)相对较近的地点配置Far Sync实例，主库(Primary Database)同步(synchronous)传输redo到Far Sync实例，保证零数据丢失（zero data loss），同时主库和Far Sync距离较近，网络延时很小，因此对主库性能影响很小。然后Far Sync实例再将redo异步(asynchronous)发送到终端备库(Standby Database)。如果redo 传输采用Maximum Performance模式，我们可以在距离生产中心(Primary Database)相对较近的地点配置Far Sync实例，主库(Primary Database) 异步传输redo到Far Sync实例，然后Far Sync实例再负责传输redo到其他多个终端备库(Standby Database)。这样可以减少主库向多个终端备库(Standby Database)传输redo的压力（offload）。 Far Sync配置对于Data Guard 角色转换(role transitions)是透明的，即switchover/failover命令方式与12c之前相同。
1.主库配置fra

SQL> alter system set DB_RECOVERY_FILE_DEST_SIZE=200G;
System altered.
SQL> alter system set db_recovery_file_dest='/u01/app/oracle/fast_recovery_area';
System altered.

2.启用归档模式和强制日志

SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  4585912 bytes
Variable Size             671090248 bytes
Database Buffers         1828716544 bytes
Redo Buffers               12189696 bytes
Database mounted.
SQL> alter database archivelog;
Database altered.
SQL> alter database force logging;
Database altered.
SQL> alter database open;
Database altered.

3.主机规划

192.168.137.121  ora1221   --->主库(ORCL12C)
192.168.137.122  ora1222   --->Far Sync实例(ORCL12CFS)
192.168.137.123  ora1223   --->备库(ORCL12CDG)

4.tns配置

ORCL12C =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = ora1221)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl12c)
    )
  )
ORCL12CDG =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = ora1223)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl12c)
    )
  )
ORCL12CFS =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = ora1222)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl12c)
    )
  )

5.参数文件配置

--主库
db_unique_name='orcl12c'
service_names='orcl12c'
log_archive_dest_1='LOCATION=USE_DB_RECOVERY_FILE_DEST valid_for=(all_logfiles,all_roles) db_unique_name=orcl12c'
log_archive_dest_2='service=orcl12cfs lgwr  sync  AFFIRM MAX_FAILURE=1 ALTERNATE=LOG_ARCHIVE_DEST_3 valid_for=(online_logfiles,primary_role) db_unique_name=orcl12cfs'
LOG_ARCHIVE_DEST_3='SERVICE=orcl12cdg  lgwr ASYNC ALTERNATE=LOG_ARCHIVE_DEST_2 VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLE) DB_UNIQUE_NAME=orcl12cdg'
LOG_ARCHIVE_DEST_STATE_3=ALTERNATE
log_archive_config='dg_config=(orcl12c,orcl12cdg,orcl12cfs)'
standby_file_management=auto
db_file_name_convert='/u01/app/oracle/oradata/orcl12c/','/u01/app/oracle/oradata/orcl12c/'
log_file_name_convert='/u01/app/oracle/oradata/orcl12c/','/u01/app/oracle/oradata/orcl12c/'
fal_server='orcl12cdg','orcl12cfs'
--Far Sync实例
db_unique_name='orcl12cfs'
service_names='orcl12c'
log_archive_dest_1='LOCATION=USE_DB_RECOVERY_FILE_DEST valid_for=(all_logfiles,all_roles) db_unique_name=orcl12cfs'
log_archive_dest_2='service=orcl12cdg lgwr  async valid_for=(STANDBY_LOGFILES,STANDBY_ROLE) db_unique_name=orcl12cdg'
log_archive_config='dg_config=(orcl12c,orcl12cdg,orcl12cfs)'
standby_file_management=manual
fal_server='orcl12c'
--备库
db_unique_name='orcl12cdg'
service_names='orcl12c'
log_archive_dest_1='LOCATION=USE_DB_RECOVERY_FILE_DEST valid_for=(all_logfiles,all_roles) db_unique_name=orcl12cdg'
log_archive_dest_2='service=orcl12c lgwr  async   valid_for=(online_logfiles,primary_role) db_unique_name=orcl12c'
log_archive_config='dg_config=(orcl12c,orcl12cdg,orcl12cfs)'
standby_file_management=auto
db_file_name_convert='/u01/app/oracle/oradata/orcl12c/','/u01/app/oracle/oradata/orcl12c/'
log_file_name_convert='/u01/app/oracle/oradata/orcl12c/','/u01/app/oracle/oradata/orcl12c/'
fal_server='orcl12c','orcl12cfs'

6.密码文件
拷贝主库的密码文件到Far Sync实例和备库$ORACLE_HOME/dbs下(如果是win在%ORACLE_HOME%/database中)

7.创建Far Sync实例
创建和参数文件匹配的fra,adump目录

--主库
ALTER DATABASE CREATE FAR SYNC INSTANCE CONTROLFILE AS '/tmp/controlfs01.ctl';
拷贝到Far Sync实例对应的控制文件位置
--Far Sync实例
startup pfile='/tmp/pfile' mount
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 10 '/u01/app/oracle/oradata/orcl12c/std_redo10.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 11 '/u01/app/oracle/oradata/orcl12c/std_redo11.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 12 '/u01/app/oracle/oradata/orcl12c/std_redo12.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 13 '/u01/app/oracle/oradata/orcl12c/std_redo13.log' size 50m reuse;
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT  LOGFILE DISCONNECT FROM SESSION;

8.创建备库
创建和参数文件匹配的fra,adump目录

--主库备份（传输至备库）
backup database format '/tmp/ora12c_%U';
--主库创建standby ctl（传输至备库和备库参数文件路径一致）
alter database create standby controlfile as '/tmp/controlst.ctl';
--启动备库至mount
startup pfile='/tmp/pfile' mount;
--备库注册备份
catalog start with '/tmp/xifenfei/';
--备库还原数据文件并恢复
restore database;
recover database;
--增加standby redo
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 10 '/u01/app/oracle/oradata/orcl12c/std_redo10.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 11 '/u01/app/oracle/oradata/orcl12c/std_redo11.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 12 '/u01/app/oracle/oradata/orcl12c/std_redo12.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 13 '/u01/app/oracle/oradata/orcl12c/std_redo13.log' size 50m reuse;
--备库开启mrp进程
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT  LOGFILE DISCONNECT FROM SESSION;
--主库增加standby redo
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 10 '/u01/app/oracle/oradata/orcl12c/std_redo10.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 11 '/u01/app/oracle/oradata/orcl12c/std_redo11.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 12 '/u01/app/oracle/oradata/orcl12c/std_redo12.log' size 50m reuse;
ALTER DATABASE ADD STANDBY LOGFILE thread 1  GROUP 13 '/u01/app/oracle/oradata/orcl12c/std_redo13.log' size 50m reuse;

9.配置结果

SQL> select * from V$DATAGUARD_CONFIG;
DB_UNIQUE_NAME                 PARENT_DBUN                    DEST_ROLE         CURRENT_SCN     CON_ID
------------------------------ ------------------------------ ----------------- ----------- ----------
orcl12c                        NONE                           PRIMARY DATABASE      1950551          0
orcl12cfs                      orcl12c                        FAR SYNC INSTANCE     1950390          0
orcl12cdg                      orcl12cfs                      PHYSICAL STANDBY      1950390          0
SQL> select group#, status, thread#, sequence#, first_change#, next_change# from v$standby_log;
    GROUP# STATUS        THREAD#  SEQUENCE# FIRST_CHANGE# NEXT_CHANGE#
---------- ---------- ---------- ---------- ------------- ------------
        10 ACTIVE              1         27       1863140
        11 UNASSIGNED          1          0
        12 UNASSIGNED          1          0
        13 UNASSIGNED          1          0
SQL> select PROTECTION_MODE,PROTECTION_LEVEL from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
-------------------- --------------------
MAXIMUM PERFORMANCE  MAXIMUM PERFORMANCE

10.调整保护级别
从MAXIMUM PERFORMANCE调整为MAXIMUM AVAILABILITY

--主库
SQL> startup mount;
ORACLE instance started.
Total System Global Area 2516582400 bytes
Fixed Size                  4585912 bytes
Variable Size             671090248 bytes
Database Buffers         1828716544 bytes
Redo Buffers               12189696 bytes
Database mounted.
SQL> alter database set standby database to maximize availability;
Database altered.
SQL>  select PROTECTION_MODE,PROTECTION_LEVEL from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
-------------------- --------------------
MAXIMUM AVAILABILITY UNPROTECTED
SQL> alter database open;
Database altered.
SQL>  select PROTECTION_MODE,PROTECTION_LEVEL from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
-------------------- --------------------
MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY
--Far Sync实例
SQL>  select PROTECTION_MODE,PROTECTION_LEVEL from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
-------------------- --------------------
MAXIMUM AVAILABILITY MAXIMUM AVAILABILITY
--备库
SQL> select PROTECTION_MODE,PROTECTION_LEVEL from v$database;
PROTECTION_MODE      PROTECTION_LEVEL
-------------------- --------------------
MAXIMUM AVAILABILITY RESYNCHRONIZATION

分类目录归档：ORACLE 12C