[Linux-cluster] GFS and CLVM-snapshot

[Kenji Wakamiya]

David Teigland wrote:
> If the NetApp has block-level snapshots, that would be an excellent
> solution (better than any kind of host-based snapshots).

 From what I've heard, apparently NetApp has LUN-level snapshots.
That sounds promising!

> [root at va03 ~]# gfs_tool freeze /gfs
> gfs_tool: unknown mountpoint /gfs
> 
> [root at va03 ~]# gfs_tool list
> 3501862912 gnbd0 foo:a.0
> 
> [root at va03 ~]# gfs_tool freeze 3501862912
> [root at va03 ~]# gfs_tool unfreeze 3501862912

I see how it is.  It worked stably!

By the way, sometimes I get warnings from gfs_fsck for snapshot-LV,
even though I froze GFS before doing lvcreate -s.
For example, the followings are.  Is this usual thing?

   # gfs_fsck -y /dev/vg0/lv0ss0
   Initializing fsck
   Starting pass1
   Pass1 complete
   Starting pass1b
   Pass1b complete
   Starting pass1c
   Pass1c complete
   Starting pass2
   Pass2 complete
   Starting pass3
   Pass3 complete
   Starting pass4
   Found unlinked inode at 1929233
	  Adjusting freemeta block count (59 -> 60).
	  Adjusting used dinode block count (10 -> 9).
   l+f directory at 29
   Added inode #1929233 to l+f dir
   Found unlinked inode at 1800635
   Added inode #1800635 to l+f dir
   Link count inconsistent for inode 25 - 5 6
   Link count updated for inode 25
   Pass4 complete
   Starting pass5
   ondisk and fsck bitmaps differ at block 29
   Succeeded.
   used inode count inconsistent: is 9 should be 10
   free meta count inconsistent: is 60 should be 59
   Pass5 complete
   #

> The cluster components are changing radically in CVS head and don't all
> work together yet.  So, you need to checkout code from the RHEL4 or FC4
> cvs branches.

I see, I will try with FC4-test3 from now.
Thanks!

-- Kenji