RAC环境NFS挂载归档日志使用rman备份出现ORA-19625/ORA-27054错误分析
系统运行环境

OS:AIX 6100-06
DB:11.1.0.6.0 RAC
归档：挂载NFS

rman执行archive log时候报错

sql statement: alter system archive log  current
Starting backup at 25-OCT-11
current log archived
released channel: c1
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup command at 02/17/2012 13:03:51
RMAN-06059: expected archived log not found, lost of archived log compromises recoverability
ORA-19625: error identifying file /rarchlogA/1_13775_764866137.dbf
ORA-27054: NFS file system where the file is created or resides is not mounted with correct options
Additional information: 6

这里由于RAC存放归档使用了NFS文件系统,在使用rman备份归档日志执行alter system archive log current的时候发生如下错误.

相关目录挂载情况

$ df -g
Filesystem    GB blocks      Free %Used    Iused %Iused Mounted on
…………
/dev/lv_arch      50.00     43.24   14%      166     1% /arch1
oradb2:/arch2     50.00     35.31   30%      463     1% /arch2
/dev/baklv        90.00     83.82    7%       10     1% /backup
$ mount:
…………
        /dev/lv_oracle   /oracle          jfs2   Oct 14 11:27 rw,log=/dev8
         /dev/lv_arch     /arch1           jfs2   Oct 14 11:27 rw,log=/dev8
     oradb2   /arch2           /arch2           nfs3   Oct 14 11:47

通过这里可以知道,这里使用默认的参数挂载NFS,从而使得NFS在rman工作时候不能正常工作。

错误原因

From  Oracle 10G R2 , Oracle checks the options with which a NFS mount is mounted on the filesystem.
and this is done to ensure that no corruption of the database can happen as incorrectly
mounted NFS volumes can result in data corruption.
There are no single set of NFS mount options that work across all Oracle platforms
Please ensure that you have the proper mount options specified by the NAS vendor /Vendor user guide
The exact checks used for an NFS mounted disk vary between platforms but in general
the basic checks will include the following checks
a) The mount table (eg; /etc/mnttab) can be read to check the mount options
b) The NFS mount is mounted with the "hard" option
c) The mount options include rsize>=32768 and wsize>=32768
d) For RAC environments, where NFS disks are supported, the "noac" mount option is used.

解决方案
1.临时解决方案
As suggested in the bug the workaround recommended is to use the Event 10298.
alter system set events ‘10298 trace name context forever, level 32’;

2.永久解决方案
具体见：http://www.xifenfei.com/3269.html