$ ais log get --help
NAME:
   ais log get - Download logs from a selected node or the entire cluster;
                 supports downloading current logs or TAR.GZ archives.
   e.g.:
     - 'ais log get NODE_ID /tmp'                    - download the current log from NODE_ID and save it in the specified directory;
     - 'ais log get NODE_ID /tmp/out' --refresh 10   - download the current log from NODE_ID as /tmp/out
                                                       and continuously update it every 10 seconds;
     - 'ais log get cluster /tmp'                    - download TAR.GZ archives from all cluster nodes
                                                       and save them in the specified directory ('get cluster' implies '--all');
     - 'ais log get NODE_ID --all'                   - download the complete log archive (TAR.GZ) from NODE_ID;
     - 'ais log get NODE_ID --all --severity error'  - download only errors and warnings from NODE_ID;
     - 'ais log get NODE_ID --all --severity e'      - same as above.
USAGE:
   ais log get NODE_ID [OUT_FILE|OUT_DIR|-] [command options]
OPTIONS:
   --refresh value   interval for continuous monitoring;
                     valid time units: ns, us (or µs), ms, s (default), m, h
   --count value     used together with '--refresh' to limit the number of generated reports, e.g.:
                      '--refresh 10 --count 5' - run 5 times with 10s interval (default: 0)
   --severity value  log severity is either 'info' (default) or 'error', whereby error logs contain both errors and warnings, e.g.:
                     - 'ais show log NODE_ID'
                     - 'ais log show NODE_ID --severity i' - same as above
                     - 'ais show log NODE_ID --severity error' - errors and warnings only
                     - 'ais show log NODE_ID --severity w' - same as above
   --yes, -y         assume 'yes' to all questions
   --all             download all logs
   --help, -h        show help

$ ais log show --help
NAME:
   ais log show - for a given node: show its current log (use '--refresh' to update, '--help' for details)
USAGE:
   ais log show NODE_ID [command options]
OPTIONS:
   --refresh value    interval for continuous monitoring;
                      valid time units: ns, us (or µs), ms, s (default), m, h
   --count value      used together with '--refresh' to limit the number of generated reports, e.g.:
                       '--refresh 10 --count 5' - run 5 times with 10s interval (default: 0)
   --severity value   log severity is either 'info' (default) or 'error', whereby error logs contain both errors and warnings, e.g.:
                      - 'ais show log NODE_ID'
                      - 'ais log show NODE_ID --severity i' - same as above
                      - 'ais show log NODE_ID --severity error' - errors and warnings only
                      - 'ais show log NODE_ID --severity w' - same as above
   --log-flush value  can be used in combination with '--refresh' to override configured 'log.flush_time'
   --help, -h         show help

$ ais cluster download-logs --help
NAME:
   ais cluster download-logs - download log archives from all clustered nodes (one TAR.GZ per node), e.g.:
               - 'download-logs /tmp/www' - save log archives to /tmp/www directory
               - 'download-logs --severity w' - errors and warnings to system temporary directory
                 (see related: 'ais log show', 'ais log get')
USAGE:
   ais cluster download-logs [OUT_DIR] [command options]
OPTIONS:
   --severity value  log severity is either 'i' or 'info' (default, can be omitted), or 'error', whereby error logs contain
                     only errors and warnings, e.g.: '--severity info', '--severity error', '--severity e'
   --help, -h        show help