Don Armstrong <d...@debian.org> writes: > On Wed, 12 Nov 2014, lee wrote: >> what's the best way to move existing logical volumes or a whole volume >> group to new disks? >> >> The target disks cannot be installed at the same time as the source >> disks. I will have to make some sort of copy over the network to >> another machine, remove the old disks, install the new disks and put the >> copy in place. >> >> The LVs contain VMs. The VMs can be shut down during the migration. >> It's not possible to make snapshots because the VG is full. >> >> New disks will be 6x1TB RAID-5, old ones are 2x74GB RAID-1 on a >> ServeRaid 8k. No more than 6 discs can be installed at the same time. > > You can remove one of the RAID-1 drives, install 5 of the 1T drives, and > start both raids in degraded mode temporarily. Once you've done that, > add the new PVs to the VG, and pvmove. > > Alternatively, you can start with three drives in raid-5, and then grow > the array out to the additional three drives, once you've done the > migration, or have two different raid-5 arrays in the same vg. > > Alternatively, you can use an external enclosure to house the RAID1 or > RAID5 temporarily. USB is slow, but workable.
Yes, I thought about something like this. I'm not sure whether I can actually grow the RAID-5. I could create the new RAID-5 with 6 disks and then remove one to run both arrays in degraded mode to copy things over. However, I currently have dom0 on a non-LVM partition, and I want to make a single LVM partition from the new RIAD-5 with several LVs. The largest LV will be for data. I want to have more room for VMs, too, and I want to be able to increase the size of the existing LVs --- either in the future or while I am at it. I want to convert dom0 to a LV, and I'm not sure whether it's better to re-install dom0 on LV or to copy and convert the existing one somehow. I'm also not sure what limits copying with dd would introduce. I might be better off making copies of everything over the network --- with the added benefit of having a backup which I currently don't have --- and then copying everything back with something like 'cp -a'. Using 'cp -a' worked fine in the past, and I was able to boot a rescue system to install grub. I've never done that with VMs in LVs, though. When I boot a rescue system, can I still install grub in each of the LVs? I also have a spare 1TB disk which I can use in another machine to make the backups to. -- Again we must be afraid of speaking of daemons for fear that daemons might swallow us. Finally, this fear has become reasonable. -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: https://lists.debian.org/87a93vq72v....@yun.yagibdah.de
