HDD upgrade route

[stuartsjg]

Hello, I am going to need to add more storage to my freenas box which has been running faultlessly since May 2015 without any intervention other than a failed can once.

For TV, movies and music i have 4 x 2TB Seagate ES drives in RAID-Z1.

Everything else; files, photos, video editibg there is 2 x WD Red 3Tb Mirrorred.

All are running reliably with no faults or issues reported or suspected.

I need to add storage to both.

For the Z1, I will probably add 1 drive, i don't have any issues with that and expand the pool.

For the mirrored pair, I could add another 2 drives configured to give RAID10, or is this overkill and adding 1 drive and reconfiguring for a 3 disk RAIDZ1 would be more space efficient.

Just looking for forum general thoughts on reliability vs performance.

Currently, I can always saturate my 1GB connection and I feel it is responsive, whilst the hardware is perhaps not the latest and greatest, the memory and CPU don't appear taxed.

I do wonder if I am running two Z1 pools, is there advantage in a cache drive? In the hardware design guide, Joshua Paetzel states the RAM is primary cache and with me seeing mine not fully utilised if that implies I would not benefit from SSD cache.

 

[BigDave]

For the Z1, I will probably add 1 drive, i don't have any issues with that

OH NO! Don't do that!

watch this presentation, it will explain the ways that you can expand your volumes and also help you avoid
pitfalls.

 

[danb35]

For the Z1, I will probably add 1 drive, i don't have any issues with that and expand the pool.

To expand on @BigDave's comment, you can't just turn a four-disk RAIDZ1 into a five-disk RAIDZ1 (work on that capability is in progress, but I'd be surprised if we see it in FreeNAS in less than two years). If you add a single disk to that array, it will be striped with the rest of the array. When (not if) that disk fails, your entire pool will be lost.

 

[gpsguy]

Add RAM before adding L2ARC.

L2ARC uses physical RAM. Given that you only have 8 or 12GB, adding a cache drive will probably hurt your performance.

is there advantage in a cache drive?

 

[joeschmuck]

For the Z1, I will probably add 1 drive, i don't have any issues with that and expand the pool.

How much additional storage do you need? If it's only 2TB more then you could copy all your data off, destroy your pool, install the fifth drive, recreate your new pool, copy all your files back. You could also just replace all the hard drives with newer larger capacity drives but if they are only 2 yers of age and still working well, it would suck to replace them all. And if you wanted to try to think about the future, you could recreate the five pool RAIDZ1 using a 4TB drive. Yes the pool would only use 2TB of it's capacity however when the other drives start to fail you could replace those with 4TB drives and once all driver are replaced you will double your capacity.

For the mirrored pair, I could add another 2 drives configured to give RAID10, or is this overkill and adding 1 drive and reconfiguring for a 3 disk RAIDZ1 would be more space efficient.

I can see that reduncancy is not your primary concern so here I'd recommend a three drive RAIDZ1. This would expand your capacity to 5.5TB over the mirror you have at 2.7TB. I would plan for theose WD Red drives to last at least 5 years before you need to repalce them. My 2TB drives are still running after 5 years. Well I just removed them and need to place them in a backup unit. They will not sit unplugged in a corner, I want to see how long I can make them run.

I do wonder if I am running two Z1 pools, is there advantage in a cache drive?

No! Just like the others have said. It's a waste of money on your system and just adds to the complexity. If you are presently booting from a USB Flash drive then you could use a small SSD (120GB or less) as a boot device, that is all I'd recommend when it comes to a SSD for your given use case.

 

[Arwen]

In some ways, making a single pool with all your disks in a RAID-Z2 may be better. After spending a month extracting my DVDs, (and a few Blu-rays), I decided I did not want to loose them. Or the support structure, (JPEGs of cover art, the carefully organized directory structure, etc...). So I used RAID-Z2.

Later I was able to afford a backup disk that could hold everything. Less of a need for RAID-Z2, but I do like that I worry less about loss.

 

[stuartsjg]

Hi, thanks for the informative replies.

Excellent presentation, I had read thought the manual storage sections and had decided that I would double back-up and destroy the set and rebuilt with the extra drives.

I was toying with adding two drives to the Z1 pool to upgrade and rebuild as Z2 but for tv and movies, I don't think such a level of online redundancy is needed when I have external backup.

For the data in the mirror, I feel I would add 2 of WD 3TB and convert to Z2 pool for the added redundancy as that data is irreplaceable however also backed up.

I'm away to add some recommended interface cards to eBay watch list as I've maxed out the 6 on boards just now.

Boot is with USB and I do agree, no need for SSD but I can max board with RAM which I had planned to upgrade inline with the added hdds.

Will update in time with the changes which are made.

Thanks all,
Have a good Christmas :)