So I just royaly fcked up by performing a replication task.
I run two pools, a mirrored vdev1 pool with 2x1TB NVMEs (vdev1) that host all my services and a second RAIDZ2 with 4x2TB Sata SSDs (sata-pool).
Today one of the 1TB NVME died and since both drives are of the same type and age I got scared the other one would die too.
So to be careful I ran a first replication tasks to the sata-pool to backup all data and put all data into sata-poll/backup. This included the ix-application dataset
As I feared my services would go down too I wanted to unset vdev1 and switch over to sata-pool temporary until I could get my hands on a replacement drive. But since I had replicated the data to /backup Truenas wouldn’t find ix-application as it was in /backup/ix-application I decided to do another replication task for ix-application to get it into sata-pool/ix-applications.
This second replication tasked was my failure (this is completely on me). It did give me a hint that there wasn`t a root snapshot within sata-pool and thus a new one would be create but I didn’t quite understand this would replace and nuke everything.
Welp lessons learned. I’m in the processes of recovering everything that I can from vdev1 since I believe I will have to completely reinstall Truenas Scale. Luckily the sata-pool only contained Movies and Tv Shows which I own the blurays for. This will simply cost me a lot of time to get back up and running.
Just trying to understand the 1st issue since I am relatively new to TrueNAS, and also replicate my own data and application datasets to backup-disk/backup dir.
The 1st issue was solely due to services’ dataset in non-root dir of another pool?
There wouldn’t have been an issue if you had done the replication to sata-pool/backup, replaced both disks in vdev1, restored its data from sata-pool/backup, and relaunched the services from the vdev1?
Regarding the 2nd issue, I never thought of that, but it makes sense that replicating to an existing dir (including root dir) wipes out everything in that dir.
Correct, if I remember correct Truenas requires any ix-applications directory to be within the root of a pool, as it has special properties. There potentially would have been no issue if I hadn’t tried replicating everything out of sata/backup. All was fine up until that point. All data transferred as excepted and was fully accessible.
The main issue was the going ahead and trying to replicate sata-pool/backup/ix-applications into sata-pool/ix-applications. There was a pop-up specifically telling me that no root snapshot had been found and thus a new root snapshot would be create and if I want to proceed.
The issue lies in me not understanding what exactly that part would mean for the sata-pool and all it’s data as a whole.
Regarding the second point again, I agree that it makes sence, thinking about it now. I would have probably needed to create sata-pool/ix-applications myself first before replicating. Though that would have probably lead to it being replicated in sata-pool/ix-applications/ix-applications which wouldn’t have been what I wanted. Oh well I learned a couple of things that day.
