Old workstation to NAS - Is it enough for TrueNas and ECC concerns

[Dreamer]

Well
I've upgraded my workstation to a Ryzen 9 5900x and a brand new motherboard, which means that now i have my old workstation laying around
CPU: i7 7700
MB: Rog Strix z270f
Ram: DDR4 Ballstix non ecc 24 GB
PSU: Smart SE

PSU have to be replaced cause i don't feel good running my 24/7 nas on that psu. Looking at the guide on Truenas forum I've seen as recommended https://www.seasonicusa.com/G-series-450-550-650.htm although is quite outdated now so i guess i'll go for a Seasonic focus GX like my new workstation or a silentstorm cool zero. My concern is the RAM. TBH i don't want waste those 24 GB of ram just for the sake of not being ECC. Is there any way to check data integrity outside of ECC ram?

thanks

 

[artlessknave]

Is there any way to check data integrity outside of ECC ram?

zfs always checks data integrity. everything is checksummed. ECC adds another layer of safety, and is always encouraged partly because an ECC motherboard is usually server grade.

silentstorm cool zero

get a seasonic. never skimp on your PSU, especially for a server. the corsair TX or RM(i) series should also be about as capable if they are easier to get - NOT the cx.

Rog Strix z270f

while the motherboard is not a great choice, it does at least appear to have an intel NIC and a few pcie x16 (the x1 slots are basically useless for anything). it would be better to get server hardware but it's understandably hard to beat the price of "I already have this".

you can mitigate risks by putting together a backup

 

[Dreamer]

Thanks a lot for your answer
and yes I already have this is hard to beat

So i guess that since i was planning on an off site backup anyway i might as well go for non ecc and an off site backup rather than spending the off site backup budget on a new workstation

btw, do you have any advice on a reputable and cheap off site backup solution? i was thinking about kDrive

 

[artlessknave]

btw, do you have any advice on a reputable and cheap off site backup solution? i was thinking about kDrive

none at all, sorry. I just do an onsite backup to a dedicate backup server. I have a onedrive setup that I sometimes use for small things, but the cloud backup storage is too expensive to backup the whole thing.

 

[Patrick M. Hausen]

none at all, sorry. I just do an onsite backup to a dedicate backup server. I have a onedrive setup that I sometimes use for small things, but the cloud backup storage is too expensive to backup the whole thing.

Yep, even very well reputed tarsnap.com charges $0.25 / GB-month, so to backup 1 TB you are paying roughly $250 / month.

For 250€ / month you can rent this at Hetzner:

• AMD Ryzen 7 3700X Octa-Core "Matisse" (Zen2)
• 128 GB DDR4 ECC RAM
• 2 x 960 GB NVMe SSD Datacenter Edition
• 10 x 16 TB SATA 6 Gb/s Enterprise HDD; 7200 rpm (Software-RAID; Level optional)
• 1 Gbit/s Anbindung

So with 10 wide RAIDZ3 that is 116 TB of raw capacity. Usable of course less. With a 1 Gbit/s uplink and absolutely no additional cost apart from the flat 250€.

Dedicated hardware wins hands down. You don't need to *own* it when you can rent it.

Storage optimized servers at Hetzner start a bit below 100€ / month. So that's even interesting for a small business or a one man shop like a professional photographer or similar.

Install FreeBSD or Linux with ZFS, create snapshot and replication task on your TrueNAS - sleep well And save energy costs while at it.

 

[Patrick M. Hausen]

So what do I do in my private environment? The 100€ / month is still prohibitive, of course. So when I upgraded my main TrueNAS from an Atom (A2SDi) based platform to a Xeon D (X10SDV) based one, I kept the old system instead of selling it on eBay and placed it at my company's office. With permission, of course. There it's idling (mostly) and I replicate my ZFS snapshots over a VPN tunnel from my home NAS to that system at the Office.

The machine is drawing ~60 watts. That's about 50 €-ct. per day in electricity or 180 € per year. Company is fine with that.

I have another coworker with TrueNAS at home (because I talked him into it) and he's keeping the entire family photo library and now that he discovered paperless-ngx also all of his documents on that TrueNAS. So we set up a replication to that same system (mine) running at the office.

Of course mutual trust and confidentiality of all parties involved is necessary, but that solution cannot be beat by any cloud based one.

 

[Dreamer]

Is ram cache actually useful if i only use the nas as a "cold storage" for daily backups only? cause if i disable it i might be able to workaround the ecc issue

 

[Patrick M. Hausen]

Is ram cache actually useful if i only use the nas as a "cold storage" for daily backups only? cause if i disable it i might be able to workaround the ecc issue

ZFS will use the RAM as cache whether you want it or not. And even when you disable cacheing entirely with sync=always, all data will still always go through the RAM. There is no getting around the "ECC issue". Which after all is not as dramatic as it might look.

The difference between cacheing and sync=always is simply how long the data is kept in RAM before being written to disk. It will still be checksummed at all processing stages so a faulty RAM will not destroy your pool.

See this for an analysis: https://jrs-s.net/2015/02/03/will-zfs-and-non-ecc-ram-kill-your-data/

 

[artlessknave]

cause if i disable it i might be able to workaround the ecc issue

you cannot disable it. virtually all data in the system goes through RAM in some shape or form. this is why ECC is important. when you have no ECC, IIRC, there is no fix for single, or detection for double, bit errors on anything in RAM. the ARC is core to how ZFS works; the only way not to use ARC is to not use ZFS.

as patrick says, you can typically get away with no ECC just fine for home use, but ECC tends to go with server grade hardware, truenas greatly tends to be go better with server grade hardware, and you can get used server grade hardware for pretty cheap that will more than suffice for home use, with ECC RAM not really costing that much more, and so this is the recommendation, because why not be safer when you can?

on that note, 24GB isn't a bad number for a home server. 16GB is the real world recommended minimum.

something else you can do is run your first system on this until you can afford/acquire a new system more in line with truenas recommendations, and then re-purpose the old one as a backup server. no ECC in a backup system is far less of a concern, since you would generally only be going to that after a failure on the main system.

it's very important to keep in mind that [d]RAID(z) is not a backup.

 

[Dreamer]

It will still be checksummed at all processing stages

so the checksum for data integrity will check if a copied file is copied correctly even in the case of a bit flip?

 

[Patrick M. Hausen]

No. The checksum will check if a block on disk was written correctly. And if it is read correctly into memory. And if it is written out to another location correctly. ZFS and its redundancy and checksums don't know and care about files. They only care about blocks. Files are just an abstraction/presentation layer on top of that. But if all blocks are good so must be the file, right?

Read the article I linked above that explains all of this in great detail.