[Ocfs2-users] Fwd: OCFS drives not syncing

[Sunil Mushran]

On 10/05/2011 08:46 AM, Bradlee Landis wrote:
> Sorry Sunil, my email replied to you instead of the list.
>
> On Wed, Oct 5, 2011 at 10:09 AM, Sunil Mushran<sunil.mushran at oracle.com>  wrote:
>> ocfs2 is a shared disk cluster file system. It requires a shared disk.
>>
>> However, if you are only going to use 2 nodes, you could use drbd,
>> a replicating block device. To ocfs2, it appears as a shared disk.
>> Google drbd and ocfs2 for more.
>>
> So I've been confused about this the whole time I guess. So how is the
> OCFS drive shared? Is it done through OCFS, or does it require NFS?
>
> How do I access the filesystem from the other node?

The drives need to be physically shared. As in, all nodes need
to be able to concurrently read and write directly to the disk.

Two popular solutions are fiber channel and iscsi.

A fiber channel solution could be EMC disk array + FC switch +
hbas on all nodes hooked up to the switch.

An iscsi solution could be a iscsi target running on one server
with the disks. The nodes would use an iscsi initiator to access
the target. The devices will show up as regular devices (/dev/sdX)
on all nodes.

The cheapest solution would be to use drbd.