Core --> Scale

TrueNAS General
1

I am combining my Core to Scale move with a move from an old server to a new server. At present, I am kicking the tires on software, testing scripts on Scale and generally making sure that I can get the same functionality out of both Core and Scale.

That said, I am starting to think about the transition process … and I wanted to check if I can do this …

Core

  • 2 x Pools (8 x 12Tb in RaidZ2, 4 x 4Tb in RaidZ)
  • Pools are DuffleBag and Backup

Scale

  • 2 x Pools (4 x 4Tb in RaidZ2, 2 x 4Tb in Mirror)
  • Pools are DuffleBag and Backup

When I move to the new system, can I export DuffleBag and Backup pools from the Scale machine. Physically remove the Scale disks from the computer and replace them with the Core disks and then import the DuffleBag and Backup pools into the Scale setup?

The pools have different disk layouts (RaidZ2 v Mirror, size of HDDs, etc). Will that cause any problems?

The structure of the data on the two DuffleBag pools will be different and I expect that I will need to revisit my shares … but … am I missing something?

2

Hi Ruff, fancy seeing you here :grinning:

I did what you suggested, and exported before importing a new pool with the duplicate name and it was straightforward.

Just checking but are you intending to transfer any data before or after the procedure?

3

Is that Krill with the cat that keeps on taking the ‘x’?

Yeah - I could make a few small pools … DuffleBagA, DuffleBagB, DuffleBagC on my test build and export / import them to different names to test - thanks for the suggestion.

I don’t think so. The vast majority of the data is the same but I will be re-organizing my data (but that is a job for later). I will have new scripts but I will park that on a separate pool while I import the two I am bringing over.

4

Yeah, it’s the Krill with the cat taking the x loop avatar has been mine on multiple fora for the past 20 years, but this place accepts animated avatars but they are static.

I imagine that importing a pool with a duplicate name is one of the early test cases so I imagine that Scale renames the imported pool, so I don’t think you will have a problem making the move the way you plan. I think there may be an issue if you updated the pools to use the most recent ZFS version in Eel, because that is not backwards compatible, but if you are just moving the pools from Core to Scale, and then later on destroying the old scale pools and reusing the disks there shouldn’t be an issue.

I think you might want to give some thought as to the future pool vdev structure though (but I’m a newbie at all this, my advice is worth zilch compared to the old hands). ie raidz expansion is inefficient and slow, this coming from some who did four 16TB disk followed by a rebalance, don’t do it if you can avoid it.

5

I started with 8 x 4TB in RaidZ2. That was just find for my needs. Couple years later I saw 12TBs very attractively priced (with a $300 gift voucher) … so now I am 8 x 12TBs in RaidZ2 (that resliver, resliver … x 8 was painfully slow - felt like about 10 days).

I don’t (currently) feel the need for more space … I have 47TB free at the moment.