List ZFS pool capacity and fragmentation
Build a paste-ready command, then review its compatibility and effects before running it.
zpool list -o name,size,alloc,free,frag,cap,healthread-onlyno known side effects Compatibility
LinuxVerified for Linux using posix, bash, zsh syntax.
Operational knowledgereview due 2027-01-20
Requirementszpoolzpool must be installed and available on PATH.
Version supportzpool Current supported releasesVerified for linux using posix, bash, zsh syntax; consult compatibility notes for platform-specific differences.
Expected signalsNAME SIZE ALLOC FREE FRAG CAP HEALTHRepresentative successful output; values vary with the selected target and system state.
Known errorszpool: command not foundzpool is missing or is not available on PATH.
Verifyzpool list -o name,size,alloc,free,frag,cap,healthThe output matches the expected target and exits without an error.Rollback noteNot required: this command is read-only and does not change system state.
Command breakdown
01zpoolCommandRuns the zpool stage of this one-liner.
02listArgumentPasses list to zpool.
03-oOptionSelects an output file or output format for this command.
04name,size,alloc,free,frag,cap,healthArgumentPasses name,size,alloc,free,frag,cap,health to zpool.
Example input
zpool list -o name,size,alloc,free,frag,cap,health
Example output
NAME SIZE ALLOC FREE FRAG CAP HEALTH
tank 928G 312G 616G 8% 33% ONLINE
Illustrative output — exact values vary by system and data.
Official sources