RAID Cards and Backplanes

[DraconisMaximus]

I know a lot about consumer / enthusiast grade hardware and have been running TrueNAS on said hardware for years but am largely unfamiliar with server specific hardware. I am currently considering buying some refurbished Supermicro gear and am worried about single points of failure.

I have always relied on software RAID and equivocal features for disk redundancy both for cost and because of warnings that RAID card failures would destroy an entire array.

With high drive count servers, the drives generally connect through a SAS backplane to a raid card e.g https://www.supermicro.com/en/products/accessories/addon/AOM-S3108M-H8L.php

This kit specifically: https://www.ebay.com/itm/176547574313?var=476294356130

Can these be configured transparently so that if the backplane or RAID card fails I can just move the drives to a new backplane or card and keep going or would a failure destroy all data.

Also, if anyone has any "You should know this!" tips about transitioning to "Server Grade" hardware feel free to drop them here too.

[Needfuldoer]

A backplane is essentially a glorified cable, it just connects the drives to the controller. It has no bearing on the data stored on the drive.

 

If you don't use hardware RAID (which you shouldn't, it's obsolete), a RAID controller should just transparently present the drives to the operating system. If you use a software RAID like mdadm, ZFS, or Storage Spaces, any OS capable of working with them should be able to read those drives if your server dies and you bring them to another computer.

[DraconisMaximus]

Just now, Needfuldoer said:

A backplane is essentially a glorified cable, it just connects the drives to the controller. It has no bearing on the data stored on the drive.

 

If you don't use hardware RAID (which you shouldn't, it's obsolete), a RAID controller should just transparently present the drives to the operating system. If you use a software RAID like mdadm, ZFS, or Storage Spaces, any OS capable of working with them should be able to read those drives if your server dies and you bring them to another computer.

Thank you,

That is what I thought but had a hard time finding it explicitly stated.

[OddOod]

51 minutes ago, Needfuldoer said:

A backplane is essentially a glorified cable

I love this because as silly as it sounds, it's SO true!

52 minutes ago, Needfuldoer said:

don't use hardware RAID

Hard agree. 

[Windows7ge]

I agree with not using hardware RAID here. There's a time and place for it but it's being phased out in various areas for more versatile software solutions.

 

Look what I found direct from the SuperMicro manual for the stock backplane that comes with this server.

 

 

If this is what it comes with it's cool that you'll have support for NVMe 2.5" drives. Kioxia puts out some good ones but this uses a SAS expander for your other 8 drives and it daisy chains to the sas expander that comes before it. So you have an upper bandwidth limit of 8xSASIII or 12GB/s but those NVMe connectors will have a dedicated link to the motherboard. It may not be setup for you though. You might have to install your own card & cables. Should be fun for you though.

[leadeater]

6 hours ago, Windows7ge said:

If this is what it comes with it's cool that you'll have support for NVMe 2.5" drives

Any U.3 backplane supports SATA, SAS and NVMe if you are ever looking around and see something with that. U.2 does not.

[Windows7ge]

14 hours ago, leadeater said:

Any U.3 backplane supports SATA, SAS and NVMe if you are ever looking around and see something with that. U.2 does not.

Oh really? I've been having hankering to play with some KIOKSIA drives if I can get a few cheap enough. heheh.

 

I'm familiar with U.2 as NVMe in a 2.5" form factor but did not know U.3 was a standard.

[leadeater]

1 hour ago, Windows7ge said:

I'm familiar with U.2 as NVMe in a 2.5" form factor but did not know U.3 was a standard.

Good thing is U.2 NVMe devices will work in U.3 backplane and U.3 device will also work in a U.2 backplane in backwards compatibility mode.

 

U.3 is a super awesome standard.

[Windows7ge]

42 minutes ago, leadeater said:

Good thing is U.2 NVMe devices will work in U.3 backplane and U.3 device will also work in a U.2 backplane in backwards compatibility mode.

 

U.3 is a super awesome standard.

I'll look up later what U.3 does different from U.2 but both ways compatibility is always fantastic.