On Fri, 24 Apr 2015 02:00:49 PM Noah O'Donoghue wrote: > On 24 April 2015 at 12:54, Toby Corkindale <[email protected]> wrote: > > I think people were suggesting blanking each removed half of the array, > > prior to making the underlying block device encrypted, then adding and > > re-mirroring. > > Wait, you're suggesting encrypting each drive separately, and then adding > the result to a linux RAID device? > > That's.... crazy, but it might even work.
It will work. > Would be interesting to see what happens to performance considering you > have to do a different encryption operation per drive of the RAID array. For as long as LUKS has been available commonly available CPUs have been able to encrypt/decrypt significantly faster than disks can write/read. CPUs have been increasing in speed at a greater rate than disks, so I really don't think a pair of separately encrypted disks is going to take much CPU time. If you had a pair of SSDs then bulk IO wouldn't be a problem as the commonly available SSDs aren't THAT fast for bulk IO. But if you had lots of random seeks then the latency of encryption might slow things down a bit, but it would probably only be noticable in benchmark results not in real world operations. > Unfortunately it looks like it's impossible to convert an existing single > drive to a RAID drive.. Or at least the instructions here do the good old > copy from one to the other dance. > > https://wiki.archlinux.org/index.php/Convert_a_single_drive_system_to_RAID > > I suppose you could in theory do this for systems that are already RAID 1 > though.. (as Russell suggests) You can convert a BTRFS filesystem from a single disk to RAID-1 while it's running. But upgrading to BTRFS is another step that involves downtime. I think that the best thing to do is have some scheduled down-time to convert the system to RAID-1 with encryption. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/ _______________________________________________ luv-main mailing list [email protected] http://lists.luv.asn.au/listinfo/luv-main
