Corruption in Mirror

[DeletedUser080302028]

I'm quite new to FreeNAS and I'm perplexed by an issue I'm having with a mirror of two 8TB disks. If data corruption occurs on one disk, shouldn't FreeNAS automatically correct it using data from the other disk? Why is it stating, "Permanent error have been detected[...]?"

 

[nightshade00013]

It will attempt to make repairs during a scrub but there are no guarantee's. It could also have been an in ram on the fly error that happens when ECC ram is not used.


https://forums.freenas.org/index.php?threads/updated-forum-rules-4-11-17.45124/ for your reading pleasure.

Hardware information is extremely important when diagnosing problems. This includes:

• motherboard make and model
• CPU make and model
• RAM quantity
• hard drives, quantity, model numbers, and RAID configuration
• hard disk controllers
• network cards

 

[rs225]

Have you checked the SMART data on both drives? Did one of the drives spend some time offline? Perhaps those errors will disappear after the scrub.

 

[Ericloewe]

Well, the corruption won't disappear...

shouldn't FreeNAS automatically correct it using data from the other disk?

There are many scenarios that can still cause data loss. Some of them can be mitigated with dual parity, as in RAIDZ2.

It's hard to meaningfully speculate without knowing more about the server.