[CentOS] who uses Lustre in production with virtual machines?

Thu Aug 5 15:04:16 UTC 2010
Todd Denniston <Todd.Denniston at tsb.cranrdte.navy.mil>

Emmanuel Noobadmin wrote, On 08/05/2010 12:40 AM:
> That's the thing, I don't think I can tolerate a slightly behind copy
> on the system. The transaction once done, must remain done. A
> situation where a node fails right after a transaction was done and
> output to user, then recovered to a slightly behind state where the
> same transaction is then not done or not recorded, is not acceptable
> for many types of transaction.
> 

You speak of transactions in a way that makes me think you are dealing with databases.
If this is the case, then I suggest you take a few searches over to the drbd archives** and look for
database issues, IIRC in some cases you are better off (speed and admin understanding/sanity)
letting the database's built in replication handle the server to server database transactional sync
than to trust a file system or even drbd to do it, because  the db engine can/will make sure the
backup db server ALSO has the data before reporting the transaction done.
Not saying that having the DB on top of gluster or DRBD too would be bad, just suggesting that you
may want to have the DB backed by something that fully understands the transactions.

** http://lists.linbit.com/pipermail/drbd-user/
-- 
Todd Denniston
Crane Division, Naval Surface Warfare Center (NSWC Crane)
Harnessing the Power of Technology for the Warfighter