@0x7700e6 @privateger getting back at this I went through the Arch Wiki page of badblocks and found a recommendation for a faster alternative, as I need to have a NAS up and running within roughly the next two weeks. I have no idea how long a badblocks test will take for 4x 8TB drives - an estimate formula I found/made for one 8TB drive: (8000000/(255/2)*2)/60/60/24≈1,5 days. No idea if that is even remotely accurate and I don't know the bandwidth of the controller for running this on 4 drives at once. (Formula explanation: (disk size/(max disk transfer speed/2 [for a somewhat average transfer speed])*2 [for a full write and read])/60 [conversion into minutes]/60 [conversion into hours]/24 [conversion into days])Also I have no idea how long it will take to build the pool and after that I still need time to transfer all the files to the NAS over a 1G network.Can you give me an idea if that estimate is somewhat accurate? Should I just try the presumably faster method the Arch Wiki lists?Did I miss anything?