Mike DeMarco wrote: >> Mike DeMarco wrote: >> >>> I currently have a zpool with two 8Gbyte disks in >>> >> it. I need to replace them with a single 56Gbyte >> disk. >> >>> with veritas I would just add the disk in as a >>> >> mirror and break off the other plex then destroy it. >> >>> I see no way of being able to do this with zfs. >>> >>> Being able to migrate data without having to >>> >> unmount and remount filesystems is very >> >>> important to me. >>> >>> Can anyone say when such functionality will be >>> >> implemented? >> >>> >>> >> If the original pool is a mirror, the it is trivial >> and has been a >> features since day one. zpool attach the new disk. >> zpool detach the old disks. >> >> If the original pool is not a mirror, then it can get >> more >> complicated, but depends on what you want it to look >> like in the long term... >> -- richard >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss@opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discu >> ss >> > > original pool is not a mirror it consists of two disks concat. (SANS disks > mirrored on SANS) > Looks like attach will only allow attacment to a single device in a zpool and > not to both devices. If I attach to one of the two devices it will grow the > pool into the whole device and then I can not remove the other device. I find > this to be a most frustrating problem with zfs and wonder if any work is > being done to correct such a omission. > >
One solution is to split the new disk into two slices. Then attach each of the old disks to a different slice. This can be done with zero downtime. If you can handle a short downtime, then you can copy to a new, single slice file system. Today, ZFS treats the top-level vdevs as dynamic stripes, but there is no notion of a second-level dynamic stripe. On the one hand, this greatly simplifies data management. On the other hand, moving from two to one device exposes the top-level stripe. -- richard _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
