On 08/06/15 20:28, Pierre Wieser wrote: > Hi all, > > I currently have an almost full RAID 5 built with 4 x 2 TB disks. > I wonder if it would be possible to migrate it to a bigger RAID 5 > with 3 x 6TB new disks. > Do you have a spare (I presume SATA) disk port? > I've imagined something like that : > - successively fail, remove a 2TB disk, add a 4TB disk, wait for end of recovery on three 2TB disks If you've got a spare port, the newer mdadm's have, I believe, a "clone and replace" option. Much better than failing then rebuilding. If not, is it worth getting a SATA expansion board? If you've not got a specialist mobo, surely a board is only going to cost a tenner or so, and quality isn't *that* important seeing as it's only a temporary measure. > - at the end of this first phase, I have the same ~6TB RAID 5 clean group with 3 x 4TB + 1 x 2TB disks > - declare the last 2 TB disk faulty and remove it > - the RAID 5 group state goes to clean, degraded > - grow the RAID 5 group with --size=max option > - grow the RAID 5 group with --array-size=~12TB option > - last, grow the RAID 5 group with --raid-devices=3 and --backup-file=... options. > > And I have tested it on a small test RAID 5 group. > As expected, this last command makes the RAID 5 group begins a reshaping operation. > But this one keeps stucked at zero. > > So I have several questions : > Don't think I've answered any of them, but I might have raised new ones. I just hope the tip saves you a bit of time. Cheers, Wol -- 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
