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标题：-bash: /bin/rm: Argument list too long
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
linux批量删除大量文件,当使用rm -rf *报-bash: /bin/rm: Argument list too long错误可以使用find+xargs搞定
[grid@xifenfei audit]$ rm -rf +ASM2_ora_1*_2017*.aud -bash: /bin/rm: Argument list too long [grid@xifenfei audit]$ ls|wc -l 111650450 [grid@xifenfei audit]$ find ./ -name "*.aud" |xargs rm -r [grid@xifenfei audit]$ ls [grid@xifenfei audit]$
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：Using mlock ulimits for SHM_HUGETLB is deprecated
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
Oracle 数据库运行在linux 6中,启用大页之后,我们经常在/var/log/messages里面会看到类似这样的记录:Mar 11 12:12:33 i-q2ghx82t kernel: oracle (3677): Using mlock ulimits for SHM_HUGETLB is deprecated,我这里的环境也有重现该问题
环境说明
--系统配置 [root@i-q2ghx82t ~]# more /etc/issue CentOS release 6.8 (Final) Kernel \r on an \m [root@i-q2ghx82t ~]# ulimit -a core file size (blocks, -c) 0 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 128331 max locked memory (kbytes, -l) 64 max memory size (kbytes, -m) unlimited open files (-n) 1024 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 10240 cpu time (seconds, -t) unlimited max user processes (-u) 128331 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited [oracle@i-q2ghx82t ~]$ cat /proc/meminfo|grep Hu AnonHugePages: 0 kB HugePages_Total: 10752 HugePages_Free: 10752 HugePages_Rsvd: 0 HugePages_Surp: 0 Hugepagesize: 2048 kB [root@i-q2ghx82t ~]# more /proc/sys/vm/hugetlb_shm_group [root@i-q2ghx82t ~]# id oracle uid=1000(oracle) gid=1000(oinstall) groups=1000(oinstall),1001(dba),1002(oper),1005(asmdba) --数据库参数 use_large_pages=only
在本环境中数据库启动正常,大页也可以正常使用,但是在系统日志中有类似Mar 11 12:12:33 i-q2ghx82t kernel: oracle (3677): Using mlock ulimits for SHM_HUGETLB is deprecated 这样的告警.通过分析,是由于少配置了hugetlb_shm_group参数导致(vm.hugetlb_shm_group 参数设置为有权使用 HugePages 的操作系统组。默认情况下，此参数设置为 0，从而允许所有组使用 HugePages。可以将此参数设置为 Oracle 数据库进程所属的操作系统组，如 oinstall),在本系统中在sysctl.conf中增加vm.hugetlb_shm_group=1000,然后重启系统(测试中,如果只是重启数据库,非系统重启后第一次重启数据库,不会出现该告警),系统日志没有出现相关告警.
在Linux 6中配置大页建议加上对应的hugetlb_shm_group参数
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：redhat和oracle linux kernel对应关系
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
|
Red Hat Enterprise Linux Version / Update |
Red Hat Enterprise Linux – Kernel version / redhat-release string |
Oracle Linux – Kernel version / release strings |
|
Red Hat Enterprise Linux 7 |
|
|
|
Red Hat Enterprise Linux 7 Update 6 |
3.10.0-957.el7.x86_64 |
4.14.35-1818.3.3.el7uek.x86_64 ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 7 Update 5 |
3.10.0-862.el7.x86_64 |
4.1.12-112.16.4.el7uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 7 Update 4 |
3.10.0-693.el7.x86_64 |
4.1.12-94.3.9.el7uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 7 Update 3 |
3.10.0-514.el7.x86_64 |
4.1.12-61.1.18.el7uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 7 Update 2 |
3.10.0-327.el7.x86_64 |
3.8.13-98.6.1.el7uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 7 Update 1 |
3.10.0-229.el7.x86_64 |
3.8.13-55.1.6.el7uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 7 GA |
3.10.0-123.el7.x86_64 |
3.8.13-35.3.1.el7uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux 6 |
|
|
|
Red Hat Enterprise Linux Server 6 Update 10 |
2.6.32-754.el6 |
4.1.12-124.16.4.el6uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 6 Update 9 |
2.6.32-696.el6 |
4.1.12-61.1.28.el6uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 6 Update 8 |
2.6.32-642.el6 |
4.1.12-37.3.1.el6uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 6 Update 7 |
2.6.32-573.el6 |
3.8.13-68.3.4.el6uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 6 Update 6 |
2.6.32-504.el6 |
3.8.13-44.1.1.el6uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 6 Update 5 |
2.6.32-431.el6 |
3.8.13-16.121.el6uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 6 Update 4 |
2.6.32-358.el6 |
2.6.39-400.17.1.el6uek ^ * |
|
Red Hat Enterprise Linux Server 6 Update 3 |
2.6.32-279.el6 |
2.6.39-200.24.1.el6uek ^ * |
|
Red Hat Enterprise Linux Server 6 Update 2 |
2.6.32-220.el6 |
2.6.32-100.34.1.el6uek ^ * |
|
Red Hat Enterprise Linux Server 6 Update 1 |
2.6.32-131.el6 |
2.6.32-100.34.1.el6uek ^ * |
|
Red Hat Enterprise Linux Server 6 GA |
2.6.32-71.el6 |
2.6.32-100.28.5.el6uek ^ * |
|
Red Hat Enterprise Linux 5 |
|
|
|
Red Hat Enterprise Linux Server 5 Update 11 |
2.6.18-398.el5 |
2.6.39-400.215.10.el5uek ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux Server 5 Update 10 |
2.6.18-371.el5
|
2.6.39-400.209.1.el5uek ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux Server 5 Update 9 |
2.6.18-348.el5 |
2.6.39-300.26.1.el5uek ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux Server 5 Update 8 |
2.6.18-308.el5 |
2.6.32-300.10.1.el5uek ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux Server 5 Update 7 |
2.6.18-274.el5 |
2.6.32-200.13.1.el5uek ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux Server 5 Update 6 |
2.6.18-238.el5 |
2.6.32-100.26.2.el5uek ^ * (x86_64 only) |
|
Red Hat Enterprise Linux Server 5 Update 5 |
2.6.18-194.el5 |
2.6.18-194.el5 ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux Server 5 Update 4 |
2.6.18-164.el5 |
2.6.18-164.el5 ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux Server 5 Update 3 |
2.6.18-128.el5 |
2.6.18-128.el5 ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux Server 5 Update 2 |
2.6.18-92.el5 |
2.6.18-92.el5 ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux Server 5 Update 1 |
2.6.18-53.el5 |
2.6.18-53.el5 ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux Server 5 GA |
2.6.18-8.el5 |
2.6.18-8.el5 ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux 4 |
|
|
|
Red Hat Enterprise Linux 4 Update 9 |
2.6.9-100.EL |
2.6.9-100.0.0.0.1.EL ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux 4 Update 8 |
2.6.9-89.EL |
2.6.9-89.0.0.0.1.EL ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux 4 Update 7 |
2.6.9-78.EL |
2.6.9-78.0.0.0.1.EL ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux 4 Update 6 |
2.6.9-67.EL |
2.6.9-67.0.0.0.1.EL ^ * (x86, x86_64, ia64) |
|
Red Hat Enterprise Linux 4 Update 5 |
2.6.9-55.EL |
2.6.9-55.0.0.0.2.EL ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux 4 Update 4 |
2.6.9-42.EL |
2.6.9-42.0.0.0.1.EL ^ * (x86, x86_64) |
|
Red Hat Enterprise Linux 4 Update 3 |
2.6.9-34.EL |
No corresponding version |
|
Red Hat Enterprise Linux 4 Update 2 |
2.6.9-22.EL |
No corresponding version |
|
Red Hat Enterprise Linux 4 Update 1 |
2.6.9-11.EL |
No corresponding version |
|
Red Hat Enterprise Linux 4 GA |
2.6.9-5.EL |
No corresponding version |
参考：Comparison of Red Hat and Oracle Linux kernel versions and release strings (文档 ID 560992.1)
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：mount: wrong fs type, bad option, bad superblock恢复Oracle
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
有朋友找到我们,说对lv进行收缩操作之后,导致文件系统无法mount,提示超级块损坏.
尝试mount失败
[root@GZGSDB data]# mount /dev/vg_gzgsdb/lv_home /home
mount: wrong fs type, bad option, bad superblock on /dev/mapper/vg_gzgsdb-lv_home,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
系统日志报错
Aug 16 21:23:24 GZGSDB kernel: EXT4-fs (dm-5): ext4_check_descriptors: Block bitmap for group 1 not in group (block 0)! Aug 16 21:23:24 GZGSDB kernel: EXT4-fs (dm-5): group descriptors corrupted!
主要操作
这里可以看出来，明显操作错误，在没有收缩文件系统之前，直接收缩的lv.
这里可以看出来，在发生故障之后，又做了很多操作，包括fsck和testdisk等,最终无法恢复,请求我们协助处理。
找出来备份超级块
[root@GZGSDB dul]# dumpe2fs /dev/vg_gzgsdb/lv_home |grep superblock dumpe2fs 1.41.12 (17-May-2010) ext2fs_read_bb_inode: A block group is missing an inode table Primary superblock at 0, Group descriptors at 1-52 Backup superblock at 32768, Group descriptors at 32769-32820 Backup superblock at 98304, Group descriptors at 98305-98356 Backup superblock at 163840, Group descriptors at 163841-163892 Backup superblock at 229376, Group descriptors at 229377-229428 Backup superblock at 294912, Group descriptors at 294913-294964 Backup superblock at 819200, Group descriptors at 819201-819252 Backup superblock at 884736, Group descriptors at 884737-884788 Backup superblock at 1605632, Group descriptors at 1605633-1605684 Backup superblock at 2654208, Group descriptors at 2654209-2654260 Backup superblock at 4096000, Group descriptors at 4096001-4096052 Backup superblock at 7962624, Group descriptors at 7962625-7962676 Backup superblock at 11239424, Group descriptors at 11239425-11239476 Backup superblock at 20480000, Group descriptors at 20480001-20480052 Backup superblock at 23887872, Group descriptors at 23887873-23887924 Backup superblock at 71663616, Group descriptors at 71663617-71663668 Backup superblock at 78675968, Group descriptors at 78675969-78676020 Backup superblock at 102400000, Group descriptors at 102400001-102400052 Backup superblock at 214990848, Group descriptors at 214990849-214990900
使用fsck修复
[root@GZGSDB data]# fsck -y /dev/vg_gzgsdb/lv_home
fsck from util-linux-ng 2.17.2
e2fsck 1.41.12 (17-May-2010)
fsck.ext4: Group descriptors look bad... trying backup blocks...
fsck.ext4: The ext2 superblock is corrupt when using the backup blocks
fsck.ext4: going back to original superblock
fsck.ext4: Device or resource busy while trying to open /dev/mapper/vg_gzgsdb-lv_home
Filesystem mounted or opened exclusively by another program?
--指定超级块恢复
[root@GZGSDB data]# fsck -y -b 102400000 /dev/vg_gzgsdb/lv_home
…………
Illegal block #0 (1296647770) in inode 354315. CLEARED.
Illegal block #1 (1398362886) in inode 354315. CLEARED.
Illegal block #3 (453538936) in inode 354315. CLEARED.
Illegal block #5 (808333361) in inode 354315. CLEARED.
Illegal block #6 (775434798) in inode 354315. CLEARED.
Illegal block #8 (1180306180) in inode 354315. CLEARED.
Illegal block #9 (1413893971) in inode 354315. CLEARED.
Illegal block #10 (1229347423) in inode 354315. CLEARED.
Illegal block #11 (1498613325) in inode 354315. CLEARED.
Illegal indirect block (1296389203) in inode 354315. CLEARED.
Inode 354315 is too big. Truncate? yes
Block #1074301965 (69632) causes directory to be too big. CLEARED.
Warning... fsck.ext4 for device /dev/mapper/vg_gzgsdb-lv_home exited with signal 11.
[root@GZGSDB data]# mount /dev/vg_gzgsdb/lv_home /home
mount: wrong fs type, bad option, bad superblock on /dev/mapper/vg_gzgsdb-lv_home,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so
至此基本上可以判断,直接修复该文件系统,让其正常mount的概率很小.直接通过lun层面来恢复.
通过工具解析lun
比较明显,客户经过一系列操作现在的现象是lv 1.03T,文件系统只有821G,明显和客户给我反馈的操作不符(应该是lv 821G),证明客户做了大量操作,已经导致文件系统损坏
由于文件系统严重异常,工具获取到的文件都是没有名称,直接从inode里面读取的数据.获取到这些数据之后,然后结合oracle的特性,判断出来对应的文件号关系(这里有大量文件重复);另外有个别文件通过inode恢复丢失,通过底层碎片重组进行恢复出来文件,然后恢复出来其中数据(asm disk header 彻底损坏恢复).这个客户比较幸运,system文件在另外一个分区中,不然工作量会大很多.
再次提醒:对lv操作一定要谨慎,特别是lvreduce操作,另外出现发生误操作之后,应该第一时间保护现场,而不是百度着去乱操作,可能导致故障更加悲剧
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：Disable Transparent HugePages
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
从redhat 6开始引入了Transparent HugePages,但是oracle一直建议disable 它,而使用标准HugePages方式.对于6和7的禁用方式有一些区别.
linux 6
修改/etc/grub.conf之后重启系统生效
vi /etc/grub.conf
title Oracle Linux Server (2.6.32-300.25.1.el6uek.x86_64)
root (hd0,0)
kernel /vmlinuz-2.6.32-300.25.1.el6uek.x86_64 ro root=LABEL=/ transparent_hugepage=never
initrd /initramfs-2.6.32-300.25.1.el6uek.x86_64.img
linux 7
修改/etc/default/grub然后执行grub2-mkconfig并重启系统生效
[root@xifenfei u01]# vi /etc/default/grub
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
GRUB_DEFAULT=saved
GRUB_DISABLE_SUBMENU=true
GRUB_TERMINAL_OUTPUT="console"
GRUB_CMDLINE_LINUX="nomodeset vconsole.font=latarcyrheb-sun16 vconsole.keymap=us crashkernel=auto
biosdevname=0 transparent_hugepage=never"
GRUB_DISABLE_RECOVERY="true"
~
[root@xifenfei u01]# grub2-mkconfig -o /boot/grub2/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.10.0-514.26.2.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-514.26.2.el7.x86_64.img
Found linux image: /boot/vmlinuz-3.10.0-123.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-123.el7.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-cb0b6b4de89a4fe4acfc8774c2f01486
Found initrd image: /boot/initramfs-0-rescue-cb0b6b4de89a4fe4acfc8774c2f01486.img
done
临时禁用
该方法对于linux 6和7均有效,不用重启系统
if test -f /sys/kernel/mm/transparent_hugepage/enabled; then echo never > /sys/kernel/mm/transparent_hugepage/enabled fi if test -f /sys/kernel/mm/transparent_hugepage/defrag; then echo never > /sys/kernel/mm/transparent_hugepage/defrag fi
联系：手机/微信(+86 17813235971) QQ(107644445)
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
创建ext4文件系统
[root@localhost ~]# mkfs.ext4 /dev/sdb1
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
1310720 inodes, 5242624 blocks
262131 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2153775104
160 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
[root@localhost ~]# mkdir /sdb
[root@localhost ~]# mount /dev/sdb1 /sdb
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/ol-root 36G 4.0G 32G 12% /
devtmpfs 1.8G 0 1.8G 0% /dev
tmpfs 1.8G 0 1.8G 0% /dev/shm
tmpfs 1.8G 8.9M 1.8G 1% /run
tmpfs 1.8G 0 1.8G 0% /sys/fs/cgroup
/dev/sda1 497M 195M 303M 40% /boot
tmpfs 369M 0 369M 0% /run/user/0
/dev/sdb1 20G 45M 19G 1% /sdb
准备测试数据
[root@localhost sdb]# cd /etc/sysctl.d/ [root@localhost sysctl.d]# ls 99-sysctl.conf [root@localhost sysctl.d]# cp 99-sysctl.conf /sdb [root@localhost sysctl.d]# more 99-sysctl.conf # System default settings live in /usr/lib/sysctl.d/00-system.conf. # To override those settings, enter new settings here, or in an /etc/sysctl.d/<name>.conf file # # For more information, see sysctl.conf(5) and sysctl.d(5).
破坏ext4文件系统
[root@localhost ~]# dd if=/dev/zero of=/dev/sdb1 bs=1024 count=5 5+0 records in 5+0 records out 5120 bytes (5.1 kB) copied, 0.00270838 s, 1.9 MB/s [root@localhost ~]# mount /dev/sdb1 /sdb mount: unknown filesystem type '(null)'
日志报错
[ 8868.362628] sd 32:0:1:0: [sdb] Cache data unavailable [ 8868.362632] sd 32:0:1:0: [sdb] Assuming drive cache: write through [ 8868.363714] sdb: sdb1 [ 8868.390297] sd 32:0:1:0: [sdb] Cache data unavailable [ 8868.390301] sd 32:0:1:0: [sdb] Assuming drive cache: write through [ 8868.391462] sdb: sdb1 [ 8900.130143] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) [ 8900.130163] SELinux: initialized (dev sdb1, type ext4), uses xattr [ 8902.803966] sdb1: WRITE SAME failed. Manually zeroing.
fsck修复
[root@localhost ~]# fsck -t ext4 /dev/sdb1 fsck from util-linux 2.23.2 e2fsck 1.42.9 (28-Dec-2013) ext2fs_open2: Bad magic number in super-block fsck.ext4: Superblock invalid, trying backup blocks... /dev/sdb1 was not cleanly unmounted, check forced. Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information Free blocks count wrong for group #1 (31740, counted=31739). Fix<y>? yes Free blocks count wrong (5116302, counted=5116301). Fix<y>? yes Free inodes count wrong for group #0 (8181, counted=8180). Fix<y>? yes Free inodes count wrong (1310709, counted=1310708). Fix<y>? yes /dev/sdb1: ***** FILE SYSTEM WAS MODIFIED ***** /dev/sdb1: 12/1310720 files (0.0% non-contiguous), 126323/5242624 blocks
测试修复结果
[root@localhost ~]# [root@localhost ~]# [root@localhost ~]# mount /dev/sdb1 /sdb [root@localhost ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/ol-root 36G 4.0G 32G 12% / devtmpfs 1.8G 0 1.8G 0% /dev tmpfs 1.8G 0 1.8G 0% /dev/shm tmpfs 1.8G 8.9M 1.8G 1% /run tmpfs 1.8G 0 1.8G 0% /sys/fs/cgroup /dev/sda1 497M 195M 303M 40% /boot tmpfs 369M 0 369M 0% /run/user/0 /dev/sdb1 20G 45M 19G 1% /sdb [root@localhost ~]# cd /sdb [root@localhost sdb]# ls 99-sysctl.conf lost+found [root@localhost sdb]# more 99-sysctl.conf # System default settings live in /usr/lib/sysctl.d/00-system.conf. # To override those settings, enter new settings here, or in an /etc/sysctl.d/<name>.conf file # # For more information, see sysctl.conf(5) and sysctl.d(5).
ext4文件系统修复
[root@localhost ~]# mkfs.ext3 /dev/sdb1
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
1310720 inodes, 5242624 blocks
262131 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
160 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
[root@localhost ~]# mount /dev/sdb1 /sdb
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/ol-root 36G 4.0G 32G 12% /
devtmpfs 1.8G 0 1.8G 0% /dev
tmpfs 1.8G 0 1.8G 0% /dev/shm
tmpfs 1.8G 8.9M 1.8G 1% /run
tmpfs 1.8G 0 1.8G 0% /sys/fs/cgroup
/dev/sda1 497M 195M 303M 40% /boot
tmpfs 369M 0 369M 0% /run/user/0
/dev/sdb1 20G 45M 19G 1% /sdb
[root@localhost ~]# dd if=/dev/zero of=/dev/sdb1 bs=1024 count=5
5+0 records in
5+0 records out
5120 bytes (5.1 kB) copied, 0.0138915 s, 369 kB/s
[root@localhost ~]# fsck -t ext3 /dev/sdb1
fsck from util-linux 2.23.2
e2fsck 1.42.9 (28-Dec-2013)
ext2fs_open2: Bad magic number in super-block
fsck.ext3: Superblock invalid, trying backup blocks...
/dev/sdb1 was not cleanly unmounted, check forced.
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
/dev/sdb1: ***** FILE SYSTEM WAS MODIFIED *****
/dev/sdb1: 11/1310720 files (0.0% non-contiguous), 126322/5242624 blocks
[root@localhost ~]# mount /dev/sdb1 /sdb
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/ol-root 36G 4.0G 32G 12% /
devtmpfs 1.8G 0 1.8G 0% /dev
tmpfs 1.8G 0 1.8G 0% /dev/shm
tmpfs 1.8G 8.9M 1.8G 1% /run
tmpfs 1.8G 0 1.8G 0% /sys/fs/cgroup
/dev/sda1 497M 195M 303M 40% /boot
tmpfs 369M 0 369M 0% /run/user/0
/dev/sdb1 20G 45M 19G 1% /sdb
fsck修复危险性较大,建议先备份对应的分区(dd命令备份分区)然后再处理,有导致分区数据全部或者部分丢失的风险,如果超级块彻底损坏无法恢复,请联系我们，提供专业ORACLE数据库恢复技术支持
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E-Mail:dba@xifenfei.com
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标题：linux 7(redhat,oracle linux,centos)中使用udev
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
慢慢的linux 7的使用人越来越多了,但是linux 7相对于5和6的版本,变动确实比较大,本文主要描写在linux 7中如何实现udev,实现设备持久化,权限和所属组的修改
linux版本
Oracle Linux Server release 7.1 [root@www.xifenfei.com ~]# uname -a Linux www.xifenfei.com 3.10.0-229.el7.x86_64 #1 SMP Fri Mar 6 04:05:24 PST 2015 x86_64 x86_64 x86_64 GNU/Linux
VMware Workstation中显示uuid需要在vmx文件中增加
disk.enableUUID = "TRUE"
查看磁盘分区
[root@www.xifenfei.com ~]# fdisk -l Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0xf60fe217 Device Boot Start End Blocks Id System /dev/sdb1 2048 2099199 1048576 83 Linux Disk /dev/sda: 42.9 GB, 42949672960 bytes, 83886080 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x000bce7c Device Boot Start End Blocks Id System /dev/sda1 2048 4204543 2101248 8e Linux LVM /dev/sda2 * 4204544 79702015 37748736 83 Linux Disk /dev/sdc: 32.2 GB, 32212254720 bytes, 62914560 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk /dev/mapper/ol-swap: 2147 MB, 2147483648 bytes, 4194304 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes
查看磁盘uuid
[root@www.xifenfei.com ~]# /usr/lib/udev/scsi_id -g -u /dev/sdb1 36000c29e91831cedbe69afe6cc08daf7 [root@www.xifenfei.com ~]# /usr/lib/udev/scsi_id -g -u /dev/sdc 36000c292495e9d9de6f21640cc7b53b9
udev绑定
[root@www.xifenfei.com ~]# more /etc/udev/rules.d/99-my-asmdevices.rules
KERNEL=="sd*[!0-9]", ENV{DEVTYPE}=="disk", SUBSYSTEM=="block", PROGRAM=="/usr/lib/udev/scsi_id -g -u -d $devnode",
RESULT=="36000c292495e9d9de6f21640cc7b53b9", RUN+="/bin/sh -c 'mknod /dev/xifenfei-sdc b $major $minor;
chown oracle:dba /dev/xifenfei-sdc; chmod 0660 /dev/xifenfei-sdc'"
KERNEL=="sd?1", SUBSYSTEM=="block", PROGRAM=="/lib/udev/scsi_id -g -u -d /dev/$parent",
RESULT=="36000c29e91831cedbe69afe6cc08daf7", SYMLINK+="xifenfei-sdb1", OWNER="oracle", GROUP="dba", MODE="0660"
绑定结果
[root@www.xifenfei.com ~]# ls -l /dev/xifenfei-* lrwxrwxrwx. 1 root root 4 Aug 7 22:49 /dev/xifenfei-sdb1 -> sdb1 brw-rw----. 1 oracle dba 8, 32 Aug 7 22:36 /dev/xifenfei-sdc [root@www.xifenfei.com ~]# ls -l /dev/sdb1 brw-rw----. 1 oracle dba 8, 17 Aug 7 22:49 /dev/sdb1
udev只修改磁盘权限
[root@www.xifenfei.com ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): n
Partition type:
p primary (1 primary, 0 extended, 3 free)
e extended
Select (default p): p
Partition number (2-4, default 2):
First sector (2099200-41943039, default 2099200):
Using default value 2099200
Last sector, +sectors or +size{K,M,G} (2099200-41943039, default 41943039): +1G
Partition 2 of type Linux and of size 1 GiB is set
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@www.xifenfei.com ~]# more /etc/udev/rules.d/99-my-asmdevices.rules
KERNEL=="sd?2", SUBSYSTEM=="block", PROGRAM=="/lib/udev/scsi_id -g -u -d /dev/$parent",
RESULT=="36000c29e91831cedbe69afe6cc08daf7", OWNER="oracle", GROUP="dba", MODE="0660"
[root@www.xifenfei.com ~]# /sbin/udevadm trigger --type=devices --action=change
[root@www.xifenfei.com ~]# ls -l /dev/sdb2
brw-rw----. 1 oracle dba 8, 18 Aug 7 23:14 /dev/sdb2
这里可以发现在linux 7中使用了两种方法绑定udev,一种是真实生成udev设备,另外一种是通过软连接实现.感谢lunar(Lunar的oracle实验室)在linux 7学习中的帮助
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：使用losetup实现linux普通文件做asm disk
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
上一篇文章《使用_asm_allow_only_raw_disks实现普通文件做asm disk》中已经介绍使用_asm_allow_only_raw_disks参数使得oracle asm可以使用文件作为asm disk,这篇文章介绍在linux中还可以通过losetup来实现文件系统模拟磁盘实现使用文件系统做asm disk的效果
通过dd构造文件
[oracle@xifenfei ~]$ mkdir /u01/oracle/oradata/asmdisk [oracle@xifenfei ~]$ dd if=/dev/zero of=/u01/oracle/oradata/asmdisk/xifenfei01.dd bs=10240k count=100 100+0 records in 100+0 records out 1048576000 bytes (1.0 GB) copied, 21.9158 seconds, 47.8 MB/s [oracle@xifenfei ~]$ dd if=/dev/zero of=/u01/oracle/oradata/asmdisk/xifenfei02.dd bs=10240k count=100 100+0 records in 100+0 records out 1048576000 bytes (1.0 GB) copied, 22.392 seconds, 46.8 MB/s [oracle@xifenfei ~]$ ls -lh /u01/oracle/oradata/asmdisk/ total 3.0G -rw-r--r-- 1 oracle oinstall 1000M Feb 27 22:58 xifenfei01.dd -rw-r--r-- 1 oracle oinstall 1000M Feb 27 23:00 xifenfei02.dd
使用losetup模拟磁盘
[root@xifenfei asmdisk]# ls -l /dev/lo log loop0 loop1 loop2 loop3 loop4 loop5 loop6 loop7 [root@xifenfei asmdisk]# losetup /dev/loop1 xifenfei01.dd [root@xifenfei asmdisk]# losetup /dev/loop2 xifenfei02.dd
使用raw实现磁盘转换为裸设备
[root@xifenfei asmdisk]# raw /dev/raw/raw10 /dev/loop1 /dev/raw/raw10: bound to major 7, minor 1 [root@xifenfei asmdisk]# raw /dev/raw/raw11 /dev/loop2 /dev/raw/raw11: bound to major 7, minor 2 [root@xifenfei asmdisk]# ls -l /dev/raw/raw1[0-1] crw------- 1 root root 162, 10 Feb 27 23:16 /dev/raw/raw10 crw------- 1 root root 162, 11 Feb 27 23:16 /dev/raw/raw11 [root@xifenfei asmdisk]# chown oracle.dba /dev/raw/raw1[0-1] [root@xifenfei asmdisk]# ls -l /dev/raw/raw1[0-1] crw------- 1 oracle dba 162, 10 Feb 27 23:16 /dev/raw/raw10 crw------- 1 oracle dba 162, 11 Feb 27 23:16 /dev/raw/raw11
创建磁盘组
[oracle@xifenfei ~]$ export ORACLE_SID=+ASM
[oracle@xifenfei ~]$ sqlplus / as sysdba
SQL*Plus: Release 10.2.0.4.0 - Production on Thu Feb 27 23:19:28 2014
Copyright (c) 1982, 2007, Oracle. All Rights Reserved.
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> create diskgroup xff external redundancy disk '/dev/raw/raw10','/dev/raw/raw11';
Diskgroup created.
SQL> select group_number,name from v$asm_diskgroup;
GROUP_NUMBER NAME
------------ ------------------------------------------------------------
1 DATA
2 XFF
SQL> select path,TOTAL_MB from v$asm_disk where group_number=2;
PATH TOTAL_MB
-------------------- ----------
/dev/raw/raw11 1000
/dev/raw/raw10 1000
通过kfed验证asm disk是数据文件
[oracle@xifenfei tmp]$ kfed read /dev/raw/raw10|grep XFF kfdhdb.dskname: XFF_0000 ; 0x028: length=8 kfdhdb.grpname: XFF ; 0x048: length=3 kfdhdb.fgname: XFF_0000 ; 0x068: length=8 [oracle@xifenfei tmp]$ kfed read /dev/raw/raw11|grep XFF kfdhdb.dskname: XFF_0001 ; 0x028: length=8 kfdhdb.grpname: XFF ; 0x048: length=3 kfdhdb.fgname: XFF_0001 ; 0x068: length=8 [oracle@xifenfei tmp]$ kfed read /u01/oracle/oradata/asmdisk/xifenfei01.dd |grep XFF kfdhdb.dskname: XFF_0000 ; 0x028: length=8 kfdhdb.grpname: XFF ; 0x048: length=3 kfdhdb.fgname: XFF_0000 ; 0x068: length=8 [oracle@xifenfei tmp]$ kfed read /u01/oracle/oradata/asmdisk/xifenfei02.dd |grep XFF kfdhdb.dskname: XFF_0001 ; 0x028: length=8 kfdhdb.grpname: XFF ; 0x048: length=3 kfdhdb.fgname: XFF_0001 ; 0x068: length=8
通过kfed命令,确定asm本质是用了dd出来的数据文件做asm disk.
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：Linux 7 新命令之—lscpu和systemctl
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
redhat 7 系列发布已经有一段时间了,最近抽时间看了下官方文档,对比了一些命令,对于其中比较关注的进行了记录,本篇主要是列出来了服务的管理改进,引进了systemctl管理和一个非常方便看cpu信息的命令lscpu
系统版本
[root@em12cdb ~]# uname -a Linux em12cdb 3.8.13-55.1.6.el7uek.x86_64 #2 SMP Wed Feb 11 14:18:22 PST 2015 x86_64 x86_64 x86_64 GNU/Linux [root@em12cdb ~]# more /etc/oracle-release Oracle Linux Server release 7.1
查看cpu信息
[root@em12cdb ~]# lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 2 On-line CPU(s) list: 0,1 Thread(s) per core: 1 Core(s) per socket: 2 Socket(s): 1 NUMA node(s): 1 Vendor ID: GenuineIntel CPU family: 6 Model: 60 Model name: Intel(R) Core(TM) i7-4790K CPU @ 4.00GHz Stepping: 3 CPU MHz: 3997.739 BogoMIPS: 7995.47 Hypervisor vendor: VMware Virtualization type: full L1d cache: 32K L1i cache: 32K L2 cache: 256K L3 cache: 8192K NUMA node0 CPU(s): 0,1
systemctl命令管理服务和开机启动
以前主要是通过/etc/init.d/或者service命令管理服务,通过chkconfig管理是否开机启动
--查看某个服务状态
[root@em12cdb ~]# systemctl status crond.service
crond.service - Command Scheduler
Loaded: loaded (/usr/lib/systemd/system/crond.service; enabled)
Active: active (running) since Mon 2015-07-27 11:59:16 CST; 1 months 7 days ago
Main PID: 1245 (crond)
CGroup: /system.slice/crond.service
└─1245 /usr/sbin/crond -n
Jul 27 11:59:16 em12cdb systemd[1]: Started Command Scheduler.
Jul 27 11:59:16 em12cdb crond[1245]: (CRON) INFO (RANDOM_DELAY will be scaled with factor 33% if used.)
Jul 27 11:59:17 em12cdb crond[1245]: (CRON) INFO (running with inotify support)
--停止某个服务
[root@em12cdb ~]# systemctl stop crond.service
[root@em12cdb ~]# systemctl status crond.service
crond.service - Command Scheduler
Loaded: loaded (/usr/lib/systemd/system/crond.service; enabled)
Active: inactive (dead) since Thu 2015-09-03 00:27:55 CST; 2s ago
Main PID: 1245 (code=exited, status=0/SUCCESS)
Jul 27 11:59:16 em12cdb systemd[1]: Started Command Scheduler.
Jul 27 11:59:16 em12cdb crond[1245]: (CRON) INFO (RANDOM_DELAY will be scaled with factor 33% if used.)
Jul 27 11:59:17 em12cdb crond[1245]: (CRON) INFO (running with inotify support)
Sep 03 00:27:55 em12cdb systemd[1]: Stopping Command Scheduler...
Sep 03 00:27:55 em12cdb systemd[1]: Stopped Command Scheduler.
--启动某个服务
[root@em12cdb ~]# systemctl start crond.service
[root@em12cdb ~]# systemctl status crond.service
crond.service - Command Scheduler
Loaded: loaded (/usr/lib/systemd/system/crond.service; enabled)
Active: active (running) since Thu 2015-09-03 00:28:08 CST; 1s ago
Main PID: 7294 (crond)
CGroup: /system.slice/crond.service
└─7294 /usr/sbin/crond -n
Sep 03 00:28:08 em12cdb systemd[1]: Started Command Scheduler.
Sep 03 00:28:08 em12cdb crond[7294]: (CRON) INFO (RANDOM_DELAY will be scaled with factor 56% if used.)
Sep 03 00:28:09 em12cdb crond[7294]: (CRON) INFO (running with inotify support)
Sep 03 00:28:09 em12cdb crond[7294]: (CRON) INFO (@reboot jobs will be run at computer's startup.)
--重启某个服务
[root@em12cdb ~]# systemctl restart crond.service
[root@em12cdb ~]# systemctl status crond.service
crond.service - Command Scheduler
Loaded: loaded (/usr/lib/systemd/system/crond.service; enabled)
Active: active (running) since Thu 2015-09-03 00:28:24 CST; 2s ago
Main PID: 7323 (crond)
CGroup: /system.slice/crond.service
└─7323 /usr/sbin/crond -n
Sep 03 00:28:24 em12cdb systemd[1]: Starting Command Scheduler...
Sep 03 00:28:24 em12cdb systemd[1]: Started Command Scheduler.
Sep 03 00:28:24 em12cdb crond[7323]: (CRON) INFO (RANDOM_DELAY will be scaled with factor 61% if used.)
Sep 03 00:28:24 em12cdb crond[7323]: (CRON) INFO (running with inotify support)
Sep 03 00:28:24 em12cdb crond[7323]: (CRON) INFO (@reboot jobs will be run at computer's startup.)
--检查某个服务是否开机启动
[root@em12cdb ~]# systemctl is-enabled crond.service
enabled
--禁止某个服务开机启动
[root@em12cdb ~]# systemctl disable crond.service
rm '/etc/systemd/system/multi-user.target.wants/crond.service'
[root@em12cdb ~]# systemctl is-enabled crond.service
disabled
--查看所有服务开机启动情况(这里使用了grep便于说明)
[root@em12cdb ~]# systemctl list-unit-files --type service|grep cron
crond.service disabled
[root@em12cdb ~]# systemctl enable crond.service
ln -s '/usr/lib/systemd/system/crond.service' '/etc/systemd/system/multi-user.target.wants/crond.service'
[root@em12cdb ~]# systemctl list-unit-files --type service|grep cron
crond.service enabled
systemctl命令修改启动模式
以前版本中,直接通过vi修改/etc/inittab文件
--多用户图形界面 [root@em12cdb ~]# systemctl get-default graphical.target --多用户字符界面 [root@em12cdb ~]# systemctl set-default multi-user.target rm '/etc/systemd/system/default.target' ln -s '/usr/lib/systemd/system/multi-user.target' '/etc/systemd/system/default.target' [root@em12cdb ~]# systemctl get-default multi-user.target
联系：手机/微信(+86 17813235971) QQ(107644445)
标题：注意系统bug—linux在E5、E5 V2、E7 V2 cpu之上的bug 765720
作者：惜分飞©版权所有[未经本人同意,不得以任何形式转载,否则有进一步追究法律责任的权利.]
今天晚上群里面兄弟说了一个linux 6上面bug,会导致系统在运行200天以上(hardware uptime),然后进行热重启后,可能在几分钟或者几个小时内出发该bug,导致系统异常.
主要影响条件为:
Red Hat Enterprise Linux 6.1 (kernel-2.6.32-131.26.1.el6 and newer)
Red Hat Enterprise Linux 6.2 (kernel-2.6.32-220.4.2.el6 and newer)
Red Hat Enterprise Linux 6.3 (kernel-2.6.32-279 series)
Red Hat Enterprise Linux 6.4 (kernel-2.6.32-358 series)
Any Intel® Xeon® E5, Intel® Xeon® E5 v2, or Intel® Xeon® E7 v2 series processor
从这里可以看出来该问题主要影响E5、E5 V2、E7 V2 cpu上的redhat 6.1-6.4版本,在6.5版本中修复,具体参考:bug 765720
另外对已ORACLE Linux,如果使用EL Kernel影响和redhat一致,如果使用Unbreakable Enterprise Kernel则在6.2版本中进行了修复该问题。
MOS上类似文章：Oracle Linux 6 RHCK system hang: processes blocked in ext4_file_open(), pick_next_task_fair()
补充说明：
1. 在Red Hat/OEL 5.x版本中不存在。
2. 在32和64位操作系统都有可能发生
3. 鉴于该bug短期内无法修复,而且真的发生了,考虑冷重启主机,临时规避
再次提醒:系统版本选定也很重要,大家在选择Linux版本之时尽量选择避开该bug(el kernel 6.5及其以后版本,uek kernel 6.2及其以后版本)。个人倾向：如果是部署ORACLE db,而且还是redhat系列Linux,更加倾向OEL(省事,相信Oracle)