ZFS: Adding a new mirror to an existing ZFS pool

  Mirrored vdevs are great for performance and it is quite straight-forward to add a mirrored vdev to an existing pool (presumably one with one or more similar vdevs already):   zpool add [poolname] mirror [device01] [device02] [device03]   If it’s a two-way mirror you will only have two devices in the above. An example […]

Ubuntu: How to add or append a file to an existing tape backup

  Sometimes you may with to add files to an existing backup; if you issue a command like:   tar -cvf /dev/st0 backupfiles   …and the tape is not already set to the end of the previous archive you will over-write any data from the position on the tape. Use the “eom” command to move […]