Well, well, well! Here we are again. What shall I say? The plan worked almost as expected. As it turned out it was enough to use the spare HGST 4TB drive and a spare USB 3.0 2TB drive joined in a volume group to copy the remaining data.
The RAID resync was interrupted because a 2nd drive was failing (of course a SEAGATE 3TB). The failing sectors were mostly on the obnam LV, so not a big problem regarding the data, but unfortunately there’s no way to skip that LV or the files, because RAID is at the lowest level and only knows about sectors.
So I completely rebuilt the raid with the 1 remaining free HGST drive and the 3 new ones, everything fly by wire. With 4 working drives the rebuild went ahead with about 33MB/sec, as it should. After 2 days the rebuild and copying the data back was finally done. I lost my obnam backup and a few pics and movies from “movs”, but that’s about it. So I guess one could say that I got away with a slap on the wrist!
In the meantime I’ve had it with the EasyRAID SATA enclosure. There were 2 major drawbacks:
- It shuts down when idle, with a timeout too short to survive a reboot. Very nasty!
- Even if it’s turned on during POST, sometimes not all drives spun up in time or at all, so it always took several attempts to re-assemble the raid. Dunno if it is because of old age or if it’s a design flaw.
So I looked for another solution and went for an ORINOCO 4Bay USB3.0 and eSATA hard disk docking station. It’s hot-pluggable and has all the bells and whistles. From what I can tell for now, it was a good choice. It has an on/off button, but no timeout, so no more boots without the Array. Yay!
At first it didn’t seem to work at all, but only because I connected the wrong eSATA cable (that one which was dangling free behind hadante). Stupid me! Once I connected the right cable, everything went smoothly.
One more thing: The serial number reported by smartctl is not printed anywhere on the drive label 🙁 Fortunately I found the spare drive on the first attempt! Such things don’t happen often…
And now: This is how it looks like after cleaning up:
Neat, isn’t it? It’s a bit louder without a closed casing, but that’s not necessarily a bad thing ™.