[ceph-users] Re: [External Email] Re: Hardware for new OSD nodes.

Brian, Eneko, BTW, the Tyan LFF chassis we've been using has 12 x 3.5" bays in front and 2 x 2.5" SATA bays in back.  We've been using 240GB SSDs in the rear bays for mirrored boot drives, so any NVMe we add is exclusively for OSD support.  -Dave Dave Hall Binghamton University kdhall(a)binghamton.edu 607-760-2328 (Cell) 607-777-4641 (Office) On 10/23/2020 11:55 AM, Brian Topping wrote: > Yes the UEFI problem with mirrored mdraid boot is well-documented. I’ve generally been working with BIOS partition maps which do not have the single point of failure UEFI has (/boot can be mounted as mirrored, any of them can be used as non-RAID by GRUB). But BIOS maps have problems as well with volume size. > > That said, the disks are portable at that point and really don’t have deep performance bottlenecks because mirroring and striping is cheap. > > Sent from my iPhone > >> On Oct 23, 2020, at 03:54, Eneko Lacunza <elacunza(a)binovo.es> wrote: >> >> Hi Brian, >> >>> El 22/10/20 a las 18:41, Brian Topping escribió: >>> >>>>> On Oct 22, 2020, at 10:34 AM, Anthony D'Atri <anthony.datri(a)gmail.com> wrote: >>>>> - You must really be sure your raid card is dependable. (sorry but I have seen so much management problems with top-tier RAID cards I avoid them like the plague). >>>> This. >>> I’d definitely avoid a RAID card. If I can do advanced encryption with an MMX instruction, I think I can certainly trust IOMMU to handle device multiplexing from software in an efficient manner, no? mdadm RAID is just fine for me and is reliably bootable from GRUB. >>> >>> I’m not an expert in driver mechanics, but mirroring should be very low overhead at the software level. >>> >>> Once it’s software RAID, moving disks between chassis is a simple process as well. >>> >>> Apologies I didn’t make that clear earlier... >> Yes, I really like mdraid :) . Problem is BIOS/UEFI has to find a working bootable disk. I think some BIOS/UEFIs have settings for a secondary boot/UEFI bootfile, but that would have to be prepared and maintained manually, out of the mdraid10; and would only work with a total failure of the primary disk. >> >> Cheers >> >> -- >> Eneko Lacunza | +34 943 569 206 >> | elacunza(a)binovo.es >> Zuzendari teknikoa | https://www.binovo.es >> Director técnico | Astigarragako Bidea, 2 - 2º izda. >> BINOVO IT HUMAN PROJECT S.L | oficina 10-11, 20180 Oiartzun >> _______________________________________________ >> ceph-users mailing list -- ceph-users(a)ceph.io >> To unsubscribe send an email to ceph-users-leave(a)ceph.io > _______________________________________________ > ceph-users mailing list -- ceph-users(a)ceph.io > To unsubscribe send an email to ceph-users-leave(a)ceph.io