Today the disks for my new ZFS NAS arrived, rejoice! 😍

Now I ask myself: If some day one of the drives fails, how am I supposed know which of the physical ones it is? My preliminary plan is to plug them into to disk container one by one, writing down the newly appearing blkids and labeling the corresponding drive. This is somewhat time consuming, so you folks have a better idea?


  • @asciiphil
    2 years ago

    A rather more sophisticated way to identify a disk, if it’s in an enclosure that has ID LEDs, is to use sg_ses.

    The rough process for that is:

    • Run lsscsi -g to get the generic SCSI device (/dev/sgN) for the enclosure.
    • Run lsscsi -t to get the SAS address for a disk. (Not sure whether this will work if it’s a SATA enclosure; all of mine are SAS.)
    • Run sg_ses -p aes /dev/sgN | less, where /dev/sgN is the enclosure’s generic SCSI device. Look through the output to find the SAS address and, from that, get the index number of the disk.
    • Run sg_ses --set ident --index I /dev/sgN, where I is the disk index number and /dev/sgN is the enclosure’s device. This will turn on the ID LED for the disk.
    • Run sg_ses --clear ident --index I /dev/sgN to turn the LED off.

    You can also use fault instead of ident to turn on the “drive fault” LED, in case the enclosure has those but not ID LEDs.