Would it be possible for someone to do an instructional video on this plugin? I think data integrity is one really vital feature missing from unRAID and I'd love to use this plugin but I find the instructions difficult to get through and understand. Also is it possible that LT could ever add file integrity functionality into unRAID or is it simply a question of file system limitations?

17 minutes ago, ashman70 said:

Also is it possible that LT could ever add file integrity functionality into unRAID or is it simply a question of file system limitations?

 

It's already available if you use btrfs.

Right but are you recommending people use BTRFS for their arrays? I thought there were issues using BTRFS and that it was safer to use XFS?

I use it on all my servers, I find it stable enough as long as there's an UPS and server is stable (ECC is also recommended), IMO the current week point of btrfs is the fsck tool, any serious issue you'll probably need to format that disk to fix it, but data is usually recoverable by mounting the disk read-only or using btrfs restore.

 

Having said that, XFS is most likely safer, but for me being able to trust my data when something unexpected happens is more important, and while the plugin works it didn't meat my needs.

Hmm, I am considering switching from a current Synology NAS to an unRAID server, the Synology is using EXT4 and I do the scrubs once a month. I have all the data backed up from this NAS and I'll be reconstituting it from the backup, which is on another of my unRAID servers running XFS. I wan't planning on using ECC, do you run ECC on all your servers running BTRFS? This is going to be a low powered NAS running a Celeron processor.

Just now, ashman70 said:

do you run ECC on all your servers running BTRFS?

 

Yes, but I already used it before switching to btrfs, all my servers are on Supermicro X9 and X11 boards with ECC.

I see, but I could forgo ECC and still be ok using BTRFS?

It's recommend, not mandatory.

What are the drawbacks of not using ECC?

Without ECC any data can get corrupted on RAM before it's written to the disk, this can happen with any filesystem.

 

There's also some fear that running a scrub on btrfs (or zfs) with bad memory could badly corrupt your data, but from what I've read this is not very likely (but possible).

 

Google btrfs (or xfs) + ECC and you will find a lot of opinions.

So the file integrity part of BTRFS is not compromised without ECC?

 

Quote

 

So you don't need ECC like ZFS?

Strictly speaking, you don't need ECC memory for either ZFS or BTRFS. ECC memory provides error detection and correction in-memory. It would be ideal to have and use, but not all machines support it.

Not having ECC doesn't mean you shouldn't use a filesystem that provides checksums. It will still protect you from disk errors.

Car analogy: If you don't have airbags, you still wear your seat belt.

 

 

https://chrisirwin.ca/posts/btrfs-presentation/

So my main concern is data integrity, from your post it would appear that data integrity insofar as data on disk, is not compromised without ECC. I know what ECC is and what it offers, just wanted to make sure that in conjunction with BTRFS, data integrity for data on disk is still available.

 

Thanks.

1 hour ago, ashman70 said:

data on disk, is not compromised without ECC.

Until you read it, which is kind of necessary. Write once read never doesn't help much. 

 

Every piece of information the computer processes is passed through memory. An undetected bad bit on a RAM chip can cause all SORTS of havoc, even if the data on disk is just fine. It can be fine on disk, and as soon as you read it, it's corrupt, because it passed through the bad RAM chip. At that point, you don't know if it's corrupt on disk, or mangled in transmission. It could still be fine on the disk, and may read ok the second time, or not.

 

ECC is a security blanket, it gives another layer of protection. How important that is, is your call.

 

1 hour ago, ashman70 said:

I know what ECC is and what it offers, just wanted to make sure that in conjunction with BTRFS, data integrity for data on disk is still available.

 

Sure, but if you do have a bad RAM bit, the data integrity could pop a false result, causing you to think the disk was bad. Probably won't happen, but the possibility is there.

Ok so hear is my dilemma, I need to find a micro ATX socket 1155 board that supports ECC and is $150 or less. Any suggestions?

 

So far all I can find is this:  Super Micro X9SCL

Edited June 12, 20179 yr by ashman70