homelab/barbarian/DISKSHELFMAP.md

# Physical Disk Locations (DS4243)
*Updated 2024/02/28*

Each cell contains the serial number for the drive in the mapped bay.
|    | X1        | X2       | X3       | X4       |
|:--:|:---------:|:--------:|:--------:|:--------:|
| Y1 | VJGPS30X  | VK0ZD6ZY | VJG282NX | VJG2PVRX |
| Y2 | VJGR6TNX  | 2EG14YNJ | VJGJVTZX | VJG1H9UX |
| Y3 | VJGJUWNX  | 2EGXD27V | VJGJAS1X | VJG2UTUX |
| Y4 | VJGRGD2X  | 2EGL8AVV | 2EKA903X | VJGRRG9X |
| Y5 | VJGK56KX  | 2EGNPVWV | 2EKATR2X | VKH3Y3XX |
| Y6 | VLKV9N8V  | R5G4W2VV | VLKXPS1V | VKGW5YGX |

# Identify a Failing Disk
Disk Smart test errors are reported by device ID (e.g. /dev/sdw), rather than the serial number. To find the serial number associated with a particular device ID, run the following one-liner with `$dev` substituted for the device to find:

`TODO`

# Get Serial Number from part-uuid

`ls -l /dev/disk/by-partuuid` 

Will return lines for each partition device and its mapping to a `/dev/sd` Linux block device.

From there, run `smartctl -a <block device> | grep Serial` where `<block device>` is like `/dev/sdw`. 

Or, as a one-liner with `$DISK_UUID` set to the UUID to find:

`ls -l /dev/disk/by-partuuid | grep $DISK_UUID | cut -d' ' -f 11 | xargs basename | sed 's/^/\/dev\//' | xargs sudo smartctl -a | grep Serial | tr -s ' ' | cut -d' ' -f 3`

It might be possible to pull the part UUID from the `zpool status` command directly. An exercise for the reader.

# Offline and wipe the failing disk

0. Match the disk name (e.g. `/dev/sdw`) to the UUID (e.g. `13846695584571018356`). Use `lsblk --fs` for this.
1. Offline the disk: `zpool offline $pool $disk_id`
2. Wipe the disk: `wipefs $disklabel` (where `$disklabel` is like `/dev/sdw`)
3. Run `lsblk --fs` again to verify the wipe worked. If not, you'll need to run a full dd wipe with `dd if=/dev/zero of=$disklabel bs=1M`. This will take a long time as it writes zeroes across the entire drive. 
4. Physically remove the disk.

# Replace Disk in Pool
Once the failed disk has been identified and physically replaced, you should know the old drive's UUID (via `zpool status`) and the new drive's device name (via `lsblk` and deduction)

# Update Log
**Most recent first**

- *2024/02/28*: Replaced 2EKA92XX with VLKXPS1V at Y6/X3
- *2024/02/27*: Replaced VJG2T4YX with VJG282NX at Y2/X3