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)

ZFS on Linux                                       2013 FEB 28                                        zinject(8)