SOLVED FreeNAS without ECC or OMV as backup for FreeNAS. Your opinion please.

[Evertb1]

A friend of mine has a modest FreeNAS server for about six months now. It runs great but his backup plan is not all that good. All his datasets are exposed trough SMB and the only backup he makes is from shares on his Windows machine to an external USB enclosure. His backups are fully dependent on that Windows PC.

At the same time he is looking at my situation. I have replication tasks running to a FreeNAS backup server. And I also make backups to the cloud. He wants at least a FreeNAS backup server as well. Problem is that he has no budget to build another FreeNAS server. He owns an older workstation that is pretty decent equipped but is not ECC compatible. But yes, he wants to use that as FreeNAS backup server.

I am of the opinion, that as long as he has no hardware suitable for FreeNas, he would be better of to use a Linux based system, like Open Media Vault with EXT4 or so and use it as an Rsync partner for his FreeNAS server. I know from experience that it works more then OK and a Pentium CPU is more then adequate.

Problem is that he has found several sources on the WEB (even within this Forum) stating that it is OK to run FreeNAS on non ECC hardware. To bad if you ask me. So now he does not agree with me and wants to go ahead. I asked him to wait a bit while I ask the community for their opinion. So what are your thoughts on this guys?

 

[ian351c]

To start: Yes, FreeNAS runs fine with non-ECC RAM.

However, the one question you have to ask here is, "What is your data worth?"

For me, some of my data is irreplaceable, so it gets backed up to three different places. For other data, it's replaceable, but the time involved to do it would be weeks or months, which is literally $1000s of my time. So that data gets backed up to two different places. And some of my data is basically scratch, and doesn't get backed up at all.

With all that being said, my main FreeNAS box has ECC RAM. Then my main storage space is replicated locally to a different set of hard disks on the main box. All that data also goes to a backup on a portable USB enclosure via rsync. Lastly, my irreplaceable stuff goes to all those places and a cloud backup. This way I cover the disaster scenarios that matter to me in a way that makes sense to me financially.

I realize that not everyone has that kind of budget (and there are also people that probably look at my scenario and think that it's not nearly enough) but remembering to think of the value of your time to recover from a disaster is probably the biggest factor that people often overlook.

 

[Meyers]

I would always use ECC with ZFS. Check out this post:

My take on building storage arrays/servers, always use ECC it doesn't cost much more and it's not just about data resiliency either.

After doing tons of research this is my take as well.

Plus I've been a Unix Admin for over 18 years and tend to err on the side of extreme caution when it comes to data. All of my work systems use ECC of course, but I wouldn't take the risk of using ZFS on a system without ECC even on my home servers (they all have ECC).

I am of the opinion, that as long as he has no hardware suitable for FreeNas, he would be better of to use a Linux based system, like Open Media Vault with EXT4 or so and use it as an Rsync partner for his FreeNAS server.

100% agree. Personally, I would use Devuan Linux with XFS and then rclone to BackBlaze B2.

 

[danb35]

If you care about your data, you should be using ECC. That said, there's nothing about FreeNAS or ZFS that makes non-ECC RAM any more dangerous than it is for any other OS or filesystem, and ZFS will still protect your data in ways that ext2/3/4/XFS/etc. won't. If the backup box has adequate RAM, I'd put FreeNAS on it and replicate to it.

 

[toadman]

Does the windows machine he's using now run ECC? If not, then a non-ECC Freenas machine will not be any worse, and is likely better giving the checksums with ZFS.

While ECC is preferred, as folks have stated Freenas will run fine on non-ECC hardware. The trade-off is that a flipped bit on the metadata can blow up the pool. While unlikely it's possible. And/or a flipped bit in the data stored there could affect a decimal point in a financial calculation, etc.

Depends on the data and what other backups exist, etc. but go to the first question.... is it worse than the windows machine is now? I'm all for reusing existing hardware. Just know the trade-offs before you make the decision.

 

[danb35]

a flipped bit on the metadata can blow up the pool.

Only if each of the multiple (at least two, as many as six) copies of the metadata has the same problem.

And/or a flipped bit in the data stored there could affect a decimal point in a financial calculation, etc.

Only if it happens "in flight" before the data's written to disk for the first time--after that, it's checksummed so the corruption would at least be detected, and corrected if there's suitable redundancy.

 

[Heracles]

Another point for not going the path your friend thinks about is that desktop hardware is not meant to run 24x 7, nor is it meant to have that many disks, causing that much heat and vibration and more.

So ECC is not the only problem with his setup and for all of these reasons, ECC, heat, vibration, durability, nbr of drives, etc, he should not use an improvised FreeNAS as a safety.

 

[toadman]

So the options are:

(1) Status Quo. All his datasets are exposed trough SMB and the only backup he makes is from shares on his Windows machine to an external USB enclosure. His backups are fully dependent on that Windows PC.

(2) Use non-ECC hardware and make a freenas backup system

(3) Buy all new hardware for a "proper" Server

As stated... "he wants at least a FreeNAS backup server as well. Problem is that he has no budget to build another FreeNAS server. He owns an older workstation that is pretty decent equipped but is not ECC compatible. But yes, he wants to use that as FreeNAS backup server."

So... people are recommending (3) despite the fact it's ruled out in the problem statement? If we accept the question as asked, it's (1) or (2). So folks would rather see the guy continue with (1) vs do (2)? I don't see it. (2) is preferred vs (1) in my opinion.

 

[Basil Hendroff]

We harp on, on this forum about the use of ECC RAM. I'm all for it where storage matters, but we seem to forget that the act of copying from a non-ECC client to a hardened FreeNAS server carries with it a risk that data will be corrupted on the client side before it even finds its way on to the FreeNAS server. If we really want to be purists, we should be saying all clients also need to have ECC RAM installed.

(2) is preferred vs (1) in my opinion.

Agreed. Viewed from a slightly different perspective, what we are really comparing are the risks of each option:

(1) non-ECC RAM (client) + no ZFS + risks through manual intervention vs.
(2) non-ECC RAM (client) + non-ECC RAM (backup server) vs.
(3) non-ECC RAM (client)

Given (3) is out-of-scope, I'll take (2) any day. By orders of magnitude, it has a much lower risk profile that (1).

 

[Evertb1]

Its been a couple of week ago that I visited this thread because my friend has been on a wel deserved vacation. But past week we build and installed his backup server. And yes we have made the choise for FreeNAS with non ECC memory.

In the mean time I have been reading some sources about running FreeNAS/ZFS with non ECC memory. And I have come to the conclusion that there are enough arguments going around for and against using non ECC memory. At the end it comes down to make up your own mind about what you are willing to risk with non ECC memory on a FreeNAS system. And that, with well tested memory modules and good broken in HDU's, the risk level should be within the acceptable for a lot of home aplliances. I still think that using ECC memory offers you the most possible protection but you should not be to rigid about it.

As told, my friend is without any budget at the moment. But he owns the makings of a modest backupserver already. And to me one thing is really important: ANY backup is better then no backup. So we decided to build his backup server with the following components:
Boot: Corsair Force series 60 GB (I had that from a bankruptcy sales a year back were I bough 5 of hem for a wopping 50 euro's)
CPU: Intel Pentium G3240 (very suitable if you ask me)
Motherboard: Asrock B85M Pro4 (luckely with Intell Gigabit lan)
Memory: 2 x 8 GB DDR3-1600 Corsair Vegeance
HDU's 2 x 6 TB Seagate Ironwolf
PSU: Corsair CX450M (not great but it is the best we can do at the moment)
I offered him a Fractal Design Define R4 I still had "lying around".

We memtested the memory, installed FreeNAS and followed up with burning in the HDU's.
The replication tasks we have created are running fine and we also have created some cloud sync tasks. So for the time being my friend should be OK.