Snapshots to a removable drive, 2 pools?

[brianm]

This may seem a little crazy but please stay with me because I have really been thinking about a neat solution to my situation.

I have a server that I realize is small and somewhat inflexible. It is a Dell T110 II using the 4 main drive bays to run 4x2TB drives in a 2x2 mirror via a PCI controller card. I use one of the on-board SATA ports for the boot SSD and one (that used to run the DVD drive bay) I hope to use to run a quality removable hard-drive. I have 32GB of RAM installed.

My data volume needs are very small, not much video storage, mainly CAD/CAM files and software programming IDEs. I may never exceed the 4TB available in the mirror and if I approach this amount of data I will dump some of the video elsewhere.

My problem is adding a sensible backup system. Is it possible to run a second ZFS ZPOOL on a single removable hard-drive and use this drive to store snapshots/backups of the mirror? The plan would be to leave the single drive running full-time so that the cron replication system will work. I would actually use multiple removable drives rotating them periodically and storing the out-of-use drives securely. I am thinking of using a single 8TB drive to back up the 4TB (max) of data in the main pool.

Will this idea work and do you think that the removable drive system will work without causing a bunch of disc errors during the change-over?

Thanks, Brian

 

[styno]

Yes, look into replication. It is based on zfs send/receive.
You basically take a snapshot and send it over to another pool, it doesn't matter what the layout of that pool is or where it lives.

 

[brianm]

Thanks Styno,

I have read just enough of the replication documents to think the idea should work, now you have confirmed this I will dig more deeply.

One more question concerning the mechanics of the plan if you don't mind.
I intend to use a CRU hard-drive cage with two removable sled units.
Presently, if you insert one of the sleds with a drive inside nothing happens until you press a "boot" button on the cage at which point a LED begins to flash then it turns steady as the drive gets up to speed. This seems to be the only control I have of the "mount" process using the GUI.
The only GUI "umount" function seems to be the "detach volume" option.

There seems to be a strong opinion that says use the GUI if ever it is possible.

My plan would be to use one of the sled-mounted drives for two weeks or a month and then swap it for the other unit. Does the sled-mount and remove procedure above sound as though it will work or am I going to get a mass of disc errors when I change the drive? Do I need to go to the shell? Presently I am using BIOS not ACHI.