RAID status - Email

[kr55]

Hi,

Freenas generated this email:

3235 (Thu Oct 11 03:07:41 BST 2012/CTRL/CRIT) - Single-bit ECC error: ECAR=1e6d0240, ELOG=22000, ( More info in next line); critical threshold exceeded

I'm not sure where to go next. The machine is a dell R710 / 24gb ram/ 14TB ram - formatted with RAID 5. The system seems well resourced, but i'm also having a lot of issues backing up VMs to it overnight on CIFS shares.

Any help/advice would be appreciated.

 

[William Grzybowski]

What does it have to do with RAID status?

It is your ECC RAM telling you there was an error.

You mean raid 5 hardware or ZFS raidz?

What kind of issues backing up VMs?

 

[kr55]

Hi

The subject line in the email from freenas had "RAID Status" as the subject - so that's what made me mention it.

I can't see any hardware errors in the dell drac software, but what is that error telling me exactly - that i have a faulty module?

The system is formatted only at the hardware level with RAID5, then in freenas there's just a single zfs volume (unraided) and a couple of CIFS shares set up.

The VM backup problem is where i use a program called vranger to backup VMs to cifs shares on a nightly schedule. When i schedule the backup jobs, only 1 or two of the VMs complete the backup and the other VMs fail, and it looks like it's not able to connect to the CIFS shares for some reason. I can't really work out whether the issue, is disk / memory / network, etc. It's got to be something to do with this freenas machine (hardware or software) as it was working fine on a lacie 5big NAS device previously. I'm completely new to Freenas though.

 

[fracai]

As an aside, it sounds like you are running ZFS on top of a hardware RAID. ZFS likes to have direct access to the volumes and layering like this is, I think, detrimental to ZFS protecting your data.

 

[kr55]

I didn't know that. In that case, would i be better creating a UFS volume or is hardware RAID not a good idea at all with freenas? I just assumed hardware RAID would be better than software RAID.

 

[fracai]

I can't really speak to the benefits of UFS on RAID or RAID in general with FreeNAS, I just know that I've heard that ZFS on RAID isn't as effective as ZFS alone. I do know that ZFS has benefits over RAID (look up "write hole") and that when you use hardware RAID you're at the whim of the RAID controller if anything goes wrong (can you get a replacement card that will read the RAID?). With ZFS you're at the whim of the open source project (find any system that supports your pool and filesystem version). I'm not sure how much of a problem RAID card compatibility actually is, but when I was building my system I was looking for an open solution.

 

[kr55]

i guess i'm not too concerned with being dependant on a raid controller, although i get what you're saying (and thanks both for replying!) It's more the performance that i'm suffering with, so if ZFS RAID is quicker than hardware RAID then i may have to look at that. I'm not sure whether the original error message is something else (memory) or related to the raid config though.