[GPFS] mmchfs device -z yes

因為HSM 需要 Enable DMAPI，

但如果要Enable DMAPI，

要將此 filesystem 在所有的nodes 都umount 下來，

然後才 mmchfs device -z yes ，

之後在所有的node mmmount 此Device 都會有以下的 error :
irism1 1076# mmmount yentest
Tue Jun 8 20:41:25 CST 2010: mmmount: Mounting file systems ...
mount: /dev/yentest: can't read superblock

並且/var/adm/ras/mmfs.log.latest 會出現，
Tue Jun 8 20:41:25.440 2010: Command: mount yentest
Tue Jun 8 20:41:28.676 2010: Command: err 691: mount yentest

此時解決方法為：
1. check dsmwatchd Daemons
2.check /var/mmfs/etc/gpfsready Daemons .
請參考：Linux x86/x86_64 GPFS HSM client installation overview ( http://publib.boulder.ibm.com/infocenter/tsminfo/v6/index.jsp?topic=/com.ibm.itsm.hsmul.doc/c_inst_lnx_gpfs_ovw.html )
3. 手動mmmount Device( for test)
4. mmmount Device -a

PS:
現在年紀大了，
慢慢的記憶力大幅衰退...
做個筆記，以後比較不會忘記...

Enable DMAPI

GPFS V3.2.1 Concepts, Planning, and Installation Guide
GA76-0413-02

Whether or not the file system can be monitored and managed by the GPFS™ Data Management API (DMAPI) may be specified at file system creation by using the -z option on the mmcrfs command or changed at a later time by using the -z option on the mmchfs command. The default is not to enable DMAPI for the file system.

Note: A file system cannot be mounted by Windows^® if DMAPI is enabled.

For further information about DMAPI for GPFS, see the GPFS: Data Management API Guide.

Parent topic: File system creation considerations