[Linux-cluster] GFS and CLVM-snapshot

[Kenji Wakamiya]

David Teigland wrote:
> CLVM snapshots do not work with GFS, sorry.  Maybe sometime in the future.

I see.  It's a very helpful info for me.

>    node1  node2  node3 (FC3)
>     GFS    GFS    GFS
>    GNBD   GNBD   GNBD  <-- gnbd_import -n
>     |      |      |
>     +------+------+
>            |
>           GNBD  <-- gnbd_serv -n / gnbd_export -c
>           LV    <-- LVM2
>           node0 (file server: FC3)

For the time being, this setup is worthy for our use.
But in the future, we will replace GNBD with iSCSI using NetApp.
If then, LVM is not able to be used on file-server side.
So I'm expecting CLVM.  But, NetApp also might have some
block-level snapshots, I guess...

> node1-3# gfs_tool freeze /mnt/gfs
> node0#   lvcreate -s -n lv0ss0 ...
> node1-3# gfs_tool unfreeze /mnt/gfs
> node0#   gnbd_export -c -d lv0ss0 -n nbd0ss0
> node1#   gnbd_import -n -i node0
> node1#   mount -t gfs -o ro,lockproto=lock_nolock /dev/gnbd/nbd0ss0

Thank you, I tried it with CVS head of about April 8th.
I don't know why, but "gfs_tool freeze" causes the following error:
gfs_tool: unknown mountpoint /mnt/gfs

I tried also today's CVS head (cmand wasn't compiled automatically;),
but fence_tool failed (It could not create a socket).
FC4 branch was not able to be compiled on FC3 (SOCK_ZAPPED matter).
I will consider using FC4-test3.

Thanks,

-- Kenji