I’m very happy with truenas scale. I started with just 2 10 TB disks in a mirrored config for my only pool, now I want to migrate that pool to 4 physical 10 TB disks in a RAIDZ1 configuration. I only have 2 TB of data right now and conveniently I have a 4TB SSD pool on the SuperMicro server which I…

[image] stk: Do I use the GUI data replication tasks? Or should I do zfs-send to the SSD pool? Whatever floats your boat. A replication task from the GUI with the appropriate settings is probably what I would do. Tweak the settings accordingly (for example full filesystem replication if you…

Yes, they’re stored in your configuration, not on the pool, and as far as I can tell, they’re just dumb paths.

Final (?) question. I was going to use RAIDZ1 but dRAID1 looks more appropriate. You tradeoff ~50% capacity, but everything else is better (performance, rebuild time, …). So if you have large disks (mine are 12 TB), this seems appropriate for me. Am I missing anything (e.g., is there something i …

dRAID only make sense if you have multiple raidz# vdevs with hot spares, for more than 20 drives in total. And flexibility is even worse than raidz#.

Well, it almost worked! but I lost the ability to run apps I tried rebooting and no app service is running. Relevant screens are: [image] and the kubectl cluster-info said it couldn’t connect to the server on 6443 [image] I’ve attached the error output when I did a k3s server to this messag…

So I’m stuck. It says “Error in Apps Service” and it says "Application(s) have failed to start: Command ‘(‘mount’, ‘-t’, ‘zfs’, ‘main/ix-applications/k3s/kubelet’, ‘/var/lib/kubelet’)’ returned non-zero exit status 1. Doing this manually fails: root@truenas[~stk]# mount -t zfs main/ix-application…

Here is the final process with all the details and gotchas! Be sure to follow all the steps especially in moving the system dataset before you export the main pool! I decided to use dRAID1 instead of RAIDZ1 due to higher read performance, slightly slower writes, but way faster rebuild. My disks …

[image] stk: I decided to use dRAID1 instead of RAIDZ1 due to higher read performance, slightly slower writes, but way faster rebuild. My disks are huge so a Z1 rebuild would take a long time. The price I pay is giving up 50% of the capacity, so I get around 21.68 TiB from my 4 12 TB disks. T…

Thanks. Easy enough to fix now. I can just redo the process. It would be nice if there were performance numbers posted somewhere.

If performance and fast resilvering are arguments for you and you are willing to trade off 50% parity, striped mirrors are an option as well. There are not as resilient as RAIDZ2 though, i.e. two drives may fail but only one drive failure is gruanteed to not kill the pool. [image] …

Recommended way to migrate my main pool from RAID1 (2 disks) to RAIDZ1 (4 disks)

TrueNAS General

stk April 26, 2024, 6:41am 29

The solution to the apps not starting problem is described in this post. So that worked like a charm.

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Recommended way to migrate my main pool from RAID1 (2 disks) to RAIDZ1 (4 disks)

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