NAME

       zinject - ZFS Fault Injector

DESCRIPTION

       zinject  creates artificial problems in a ZFS pool by simulating data corruption or device
       failures. This program is dangerous.

SYNOPSIS

       zinject
              List injection records.

       zinject -b objset:object:level:blkd [-f frequency] [-amu] pool
              Force an error into the pool at a bookmark.

       zinject -c <id | all>
              Cancel injection records.

       zinject -d vdev -A <degrade|fault> pool
              Force a vdev into the DEGRADED or FAULTED state.

       zinject -d vdev -D latency:lanes pool

              Add an artificial delay to IO requests  on  a  particular  device,  such  that  the
              requests  take  a  minimum of 'latency' milliseconds to complete. Each delay has an
              associated number of 'lanes' which defines the number  of  concurrent  IO  requests
              that can be processed.

              For  example,  with a single lane delay of 10 ms (-D 10:1), the device will only be
              able to service a single IO request at a time with each request  taking  10  ms  to
              complete.  So,  if  only  a  single  request  is submitted every 10 ms, the average
              latency will be 10 ms; but if more than one request is submitted every 10  ms,  the
              average latency will be more than 10 ms.

              Similarly,  if  a delay of 10 ms is specified to have two lanes (-D 10:2), then the
              device will be able to service two requests at a time, each with a minimum  latency
              of  10  ms. So, if two requests are submitted every 10 ms, then the average latency
              will be 10 ms; but if more than two requests are submitted every 10 ms, the average
              latency will be more than 10 ms.

              Also  note,  these delays are additive. So two invocations of '-D 10:1', is roughly
              equivalent to a single invocation of '-D 10:2'. This also means,  one  can  specify
              multiple  lanes  with differing target latencies. For example, an invocation of '-D
              10:1' followed by '-D 25:2' will create 3 lanes on the  device;  one  lane  with  a
              latency of 10 ms and two lanes with a 25 ms latency.

       zinject -d vdev [-e device_error] [-L label_error] [-T failure] [-f frequency] [-F] pool
              Force a vdev error.

       zinject -I [-s seconds | -g txgs] pool
              Simulate a hardware failure that fails to honor a cache flush.

       zinject -p function pool
              Panic inside the specified function.

       zinject -t data [-e device_error] [-f frequency] [-l level] [-r range] [-amq] path
              Force an error into the contents of a file.

       zinject -t dnode [-e device_error] [-f frequency] [-l level] [-amq] path
              Force an error into the metadnode for a file or directory.

       zinject -t mos_type [-e device_error] [-f frequency] [-l level] [-r range] [-amqu] pool
              Force an error into the MOS of a pool.

OPTIONS

       -a     Flush the ARC before injection.

       -b objset:object:level:start:end
              Force an error into the pool at this bookmark tuple. Each number is in hexadecimal,
              and only one block can be specified.

       -d vdev
              A vdev specified by path or GUID.

       -e device_error
              Specify checksum for an ECKSUM error, dtl for an ECHILD error, io for an EIO  error
              where reopening the device will succeed, or nxio for an ENXIO error where reopening
              the device will fail.

       -f frequency
              Only inject errors a fraction of the time. Expressed as a  real  number  percentage
              between 0.0001 and 100.

       -F     Fail faster. Do fewer checks.

       -g txgs
              Run for this many transaction groups before reporting failure.

       -h     Print the usage message.

       -l level
              Inject an error at a particular block level. The default is 0.

       -L label_error
              Set the label error region to one of  nvlist,  pad1,  pad2, or  uber.

       -m     Automatically remount the underlying filesystem.

       -q     Quiet mode. Only print the handler number added.

       -r range
              Inject  an  error  over  a  particular  logical  range  of an object, which will be
              translated to the appropriate blkid range according to the object's properties.

       -s seconds
              Run for this many seconds before reporting failure.

       -T failure
              Set the failure type to one of  all,  claim,  free,  read, or  write.

       -t mos_type
              Set this to mos for any data in the MOS, mosdir for an object directory, config for
              the  pool  configuration,  bpobj for the block pointer list, spacemap for the space
              map, metaslab for the metaslab, or errlog for the persistent error log.

       -u     Unload the pool after injection.

ENVIRONMENT VARIABLES

       ZINJECT_DEBUG
              Run zinject in debug mode.

AUTHORS

       This man page was written by Darik Horn <dajhorn@vanadac.com> excerpting the zinject usage
       message and source code.

SEE ALSO

       zpool(8), zfs(8)