Background ----- My fileserver had a "bad event" last week. Shut it down normally to add a new hard drive, and it would no longer post. Tried about 50 times, doing the typical everything non-essential unplugged, trying 1 of 4 memory modules at a time, and 1 of 2 processors at a time. Got no where.
Inexpensive HP workstation, so purchased a used identical model (complete other than hard drives) on eBay. Replacement arrived today. Posts fine. Moved hard drives over (again, identical model, and Arch Linux not Windows) and it started giving "Watchdog detected hard LOCKUP" type errors I've never seen before. Decided I'd diagnose which part in the original server was bad. By sitting turned off for a week, it suddenly started posting just fine. But, with the hard drives back in it, I'm getting the same hard lockup errors. An Arch ISO DVD runs stress testing perfectly. Btrfs-specific ----- The current problem I'm having must be a bad hard drive or corrupted data. 3 drive btrfs RAID1 (data and metadata.) sda has 1GB of the 3GB of data, and 1GB of the 1GB of metadata. sda appears to be going bad, with my low threshold of "going bad", and will be replaced ASAP. It just developed 16 reallocated sectors, and has 40 current pending sectors. I'm currently running a "btrfs scrub start -B -d -r /terra", which status on another term shows me has found 32 errors after running for an hour. Question 1 - I'm expecting if I re-run the scrub without the read-only option, that it will detect from the checksum data which sector is correct, and re-write to the drive with bad sectors the data to a new sector. Correct? Question 2 - Before having ran the scrub, booting off the raid with bad sectors, would btrfs "on the fly" recognize it was getting bad sector data with the checksum being off, and checking the other drives? Or, is it expected that I could get a bad sector read in a critical piece of operating system and/or kernel, which could be causing my lockup issues? Question 3 - Probably doesn't matter, but how can I see which files (or metadata to files) the 40 current bad sectors are in? (On extX, I'd use tune2fs and debugfs to be able to see this information.) I do have hourly snapshots, from when it was properly running, so once I'm that far in the process, I can also compare the most recent snapshots, and see if there's any changes that happened to files that shouldn't have. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
