Hi Erik, A couple of questions about what you said in your email. In synopsis 2, if hostA has gone belly up and is no longer accessible, then a step that is implied (or maybe I'm just inferring it) is to go to the SAN and reassign the LUN from hostA to hostB. Correct?
----- Original Message ---- From: Erik Trimble <erik.trim...@sun.com> To: Grant Lowe <gl...@sbcglobal.net> Cc: zfs-discuss@opensolaris.org Sent: Wednesday, March 11, 2009 1:42:06 PM Subject: Re: [zfs-discuss] ZFS on a SAN I'm not 100% sure what your question here is, but let me give you a (hopefully) complete answer: (1) ZFS is NOT a clustered file system, in the sense that it is NOT possible for two hosts to have the same LUN mounted at the same time, even if both are hooked to a SAN and can normally see that LUN. (2) ZFS can do failover, however. If you have a LUN from a SAN on hostA, create a ZFS pool in it, and use as normal. Should you with to failover the LUN to hostB, you need to do a 'zpool export <zpool>' on hostA, then 'zpool import <zpool>' on hostB. If hostA has been lost completely (hung/died/etc) and you are unable to do an 'export' on it, you can force the import on hostB via 'zpool import -f <zpool>' ZFS requires that you import/export entire POOLS, not just filesystems. So, given what you seem to want, I'd recommend this: On the SAN, create (2) LUNs - one for your primary data, and one for your snapshots/backups. On hostA, create a zpool on the primary data LUN (call it zpool A), and another zpool on the backup LUN (zpool B). Take snapshots on A, then use 'zfs send' and 'zfs receive' to copy the clone/snapshot over to zpool B. then 'zpool export B' On hostB, import the snapshot pool: 'zfs import B' It might just be as easy to have two independent zpools on each host, and just do a 'zfs send' on hostA, and 'zfs receive' on hostB to copy the snapshot/clone over the wire. -Erik On Wed, 2009-03-11 at 13:18 -0700, Grant Lowe wrote: > Hi All, > > I'm new on ZFS, so I hope this isn't too basic a question. I have a host > where I setup ZFS. The Oracle DBAs did their thing and I know have a number > of ZFS datasets with their respective clones and snapshots on serverA. I > want to export some of the clones to serverB. Do I need to zone serverB to > see the same LUNs as serverA? Or does it have to have preexisting, empty > LUNs to import the clones? Please help. Thanks. > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss -- Erik Trimble Java System Support Mailstop: usca22-123 Phone: x17195 Santa Clara, CA Timezone: US/Pacific (GMT-0800) _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
