Backup pool to another local pool but turn it off.

[kschaffner]

I have an odd question that I'm having a little trouble finding an example of. I have a primary pool of 8X8TB in a RAID-Z2. I would like to back this pool up to a pool of disks that I have in a 24 bay NetApp DS4246.

I don't want the DS4246 to stay on all the time due to heat/noise. Would the best way to do this be to create a pool, use ZFS replication or rsync to kick off the copy and then detach the pool and power it off? Then when I want to update the backup just re-import the pool a week or so later to do it again as well as letting it run a scrub every 30-60 days or so?

I don't know how well FreeNAS would handle doing this.

Thanks!!

 

[artlessknave]

the DS4246 seems to be a disk shelf; I'm not sure how it connects but as long as it presents disks directly to freenas (no RAID or proprietary stuff), it should work fine.
rsync will be less elegant by far since it has to traverse every single file. replication with no changes takes minutes.
configuration replication to the same system can be a bit janky seeming but should should work fine.

 

[Glorious1]

I'm not clear if this is another server or, as artlessknave surmises, something that gets plugged in and is part of your freenas. You can replicate from one pool to another internally, if that's your goal. Mine is set up that way. It's a little confusing setting up the certificates or whatever but it works seamlessly once it's set up. I doubt there's any way around your manual intervention though if you want to keep the target offline/off otherwise.

 

[kschaffner]

It is a disk shelf that's plugged in to my server using an LSI 9201-16e HBA in IT mode. My server is in a 24 bay supermicro 846 chassis and I have the disk shelf below it. I was just wanting to backup my pool on the supermicro server's backplane to the DAS and then shut it off when it's not being used to save power and heat.

I'm thinking snapshots with zfs send/receive might be the way to go. I just didn't know if it's a good idea to power down the pool like that and just have it run while performing a backup.

 

[artlessknave]

should be fine. the only problem I can think of with powering down a pool is interrupting services on that pool, but if it is only a replication target, that ought not be a concern. there will be some wear on the disks, particularly with nas drives that are specifically designed and tuned for 24/7 operation, but a weekly, or even biweekly, spin up and shutdown shouldnt be too horrible, if you are aware of the risks (you could turn it on and have disks that died on shutdown you didnt know about) and dont care since it is a backup.
depending on exactly how this disk shelf works, you might be able to achieve your goal by setting the disks to spin right down after a certain amount of non use, allowing them to only be active for your replications and scrubs. this would depend on your ability to control things like fan speed on the shelf.

 

[kschaffner]

The disk shelf isn't smart without it's "controller" server. I am running my FreeNAS virtualized under ESXi so I could also just spin up another FreeNAS VM and pass the 9201-16e HBA to it and have an actual target I can point to, I can then just power off that FreeNAS VM and then the disk shelf.