Hi Hans, (?) On 11/30/2010 02:34 AM, hansbkk@xxxxxxxxx wrote: > On Tue, Nov 30, 2010 at 2:14 PM, Nataraj <incoming-centos@xxxxxxx> wrote: >>> TopRAID1's LVM is likely to be running over a RAID6 set , so I'm not >>> depending on the TopRAID mirroring for reliability, just using it for >>> the above volume cloning. >> >> Your raid 1 backups won't mirror any snapshots of your LV's unless you >> specifically setup mirroring of the snapshots after they exist. > > Ah, getting clearer to me, I was thinking I'd be mirroring the LV > itself, but you're right, taking a snapshot and mirroring that is a > much better idea. I think you are making this overly complex, insisting on a RAID1 operation to backup from on filer to the other. Consider having each disk on filer #2 configured as a single LVM PV/VG, so it can stand alone in a rotation. The try the alternate below. > So here's a summary of steps, please confirm: > - create a snapshot of a given volume Here's where you are over-complicating things: > - create a new RAID1 mdN between that and a physical partition (blank?) > - let that get sync'd up > - break the RAID (fail the partition?), remove the drive As an alternate, with simpler recovery semantics: Create matching LV on non-RAID PV/VG on filer #2 dd + netcat + dd or other technique to dup the snapshot on filer #1 to filer #2 > - delete the snapshot Now, you have a single disk in your backup set that can be mounted on either filer, and either copied back into service, or in an emergency, used directly (live) in filer #1. This approach also gives you the *option* to implement the backup transfer with file system conversions, compression, free space removal, or any other administrative adjustments you need. A RAID mirror can only duplicate the raw block device. HTH, Phil -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
