Description of the different events generated by the ZFS
stack.
Most of these don't have any description. The events generated by
ZFS have never been publicly documented. What is here is intended as a
starting point to provide documentation for all possible events.
To view all events created since the loading of the ZFS
infrastructure (i.e, "the module"), run
to get a full detail of the events and what information is
available about it.
This man page lists the different subclasses that are issued in
the case of an event. The full event name would be
ereport.fs.zfs.SUBCLASS, but we only list the last part here.
checksum
Issued when a checksum error has been detected.
io
Issued when there is an I/O error in a vdev in the
pool.
data
Issued when there have been data errors in the
pool.
deadman
Issued when an I/O is determined to be "hung",
this can be caused by lost completion events due to flaky hardware or drivers.
See the zfs_deadman_failmode module option description for additional
information regarding "hung" I/O detection and configuration.
delay
Issued when a completed I/O exceeds the maximum allowed
time specified by the zio_slow_io_ms module option. This can be an
indicator of problems with the underlying storage device. The number of delay
events is ratelimited by the zfs_slow_io_events_per_second module
parameter.
config.sync
Issued every time a vdev change have been done to the
pool.
zpool
Issued when a pool cannot be imported.
zpool.destroy
Issued when a pool is destroyed.
zpool.export
Issued when a pool is exported.
zpool.import
Issued when a pool is imported.
zpool.reguid
Issued when a REGUID (new unique identifier for the pool
have been regenerated) have been detected.
vdev.unknown
Issued when the vdev is unknown. Such as trying to clear
device errors on a vdev that have failed/been kicked from the system/pool and
is no longer available.
vdev.open_failed
Issued when a vdev could not be opened (because it didn't
exist for example).
vdev.corrupt_data
Issued when corrupt data have been detected on a
vdev.
vdev.no_replicas
Issued when there are no more replicas to sustain the
pool. This would lead to the pool being DEGRADED.
vdev.bad_guid_sum
Issued when a missing device in the pool have been
detected.
vdev.too_small
Issued when the system (kernel) have removed a device,
and ZFS notices that the device isn't there any more. This is usually followed
by a probe_failure event.
vdev.bad_label
Issued when the label is OK but invalid.
vdev.bad_ashift
Issued when the ashift alignment requirement has
increased.
vdev.remove
Issued when a vdev is detached from a mirror (or a spare
detached from a vdev where it have been used to replace a failed drive - only
works if the original drive have been readded).
vdev.clear
Issued when clearing device errors in a pool. Such as
running zpool clear on a device in the pool.
vdev.check
Issued when a check to see if a given vdev could be
opened is started.
vdev.spare
Issued when a spare have kicked in to replace a failed
device.
vdev.autoexpand
Issued when a vdev can be automatically expanded.
io_failure
Issued when there is an I/O failure in a vdev in the
pool.
probe_failure
Issued when a probe fails on a vdev. This would occur if
a vdev have been kicked from the system outside of ZFS (such as the kernel
have removed the device).
log_replay
Issued when the intent log cannot be replayed. The can
occur in the case of a missing or damaged log device.
resilver.start
Issued when a resilver is started.
resilver.finish
Issued when the running resilver have finished.
scrub.start
Issued when a scrub is started on a pool.
scrub.finish
Issued when a pool has finished scrubbing.
scrub.abort
Issued when a scrub is aborted on a pool.
scrub.resume
Issued when a scrub is resumed on a pool.
scrub.paused
Issued when a scrub is paused on a pool.
bootfs.vdev.attach
This is the payload (data, information) that accompanies an
event.
For zed(8), these are set to uppercase and prefixed with
ZEVENT_.
pool
Pool name.
pool_failmode
Failmode -
wait,
continue or
panic.
See
zpool(8) (
failmode property) for more information.
pool_guid
The GUID of the pool.
pool_context
The load state for the pool (0=none, 1=open, 2=import,
3=tryimport, 4=recover 5=error).
vdev_guid
The GUID of the vdev in question (the vdev failing or
operated upon with zpool clear etc).
vdev_type
Type of vdev -
disk,
file,
mirror
etc. See
zpool(8) under
Virtual Devices for more information on
possible values.
vdev_path
Full path of the vdev, including any -partX.
vdev_devid
ID of vdev (if any).
vdev_fru
Physical FRU location.
vdev_state
State of vdev (0=uninitialized, 1=closed, 2=offline,
3=removed, 4=failed to open, 5=faulted, 6=degraded, 7=healthy).
vdev_ashift
The ashift value of the vdev.
vdev_complete_ts
The time the last I/O completed for the specified
vdev.
vdev_delta_ts
The time since the last I/O completed for the specified
vdev.
vdev_spare_paths
List of spares, including full path and any
-partX.
vdev_spare_guids
GUID(s) of spares.
vdev_read_errors
How many read errors that have been detected on the
vdev.
vdev_write_errors
How many write errors that have been detected on the
vdev.
vdev_cksum_errors
How many checksum errors that have been detected on the
vdev.
parent_guid
GUID of the vdev parent.
parent_type
Type of parent. See vdev_type.
parent_path
Path of the vdev parent (if any).
parent_devid
ID of the vdev parent (if any).
zio_objset
The object set number for a given I/O.
zio_object
The object number for a given I/O.
zio_level
The indirect level for the block. Level 0 is the lowest
level and includes data blocks. Values > 0 indicate metadata blocks at the
appropriate level.
zio_blkid
The block ID for a given I/O.
zio_err
The errno for a failure when handling a given I/O. The
errno is compatible with
errno(3) with the value for EBADE (0x34) used
to indicate ZFS checksum error.
zio_offset
The offset in bytes of where to write the I/O for the
specified vdev.
zio_size
The size in bytes of the I/O.
zio_flags
The current flags describing how the I/O should be
handled. See the I/O FLAGS section for the full list of I/O
flags.
zio_stage
The current stage of the I/O in the pipeline. See the
I/O STAGES section for a full list of all the I/O stages.
zio_pipeline
The valid pipeline stages for the I/O. See the I/O
STAGES section for a full list of all the I/O stages.
zio_delay
The time elapsed (in nanoseconds) waiting for the block
layer to complete the I/O. Unlike zio_delta this does not include any
vdev queuing time and is therefore solely a measure of the block layer
performance.
zio_timestamp
The time when a given I/O was submitted.
zio_delta
The time required to service a given I/O.
prev_state
The previous state of the vdev.
cksum_expected
The expected checksum value for the block.
cksum_actual
The actual checksum value for an errant block.
cksum_algorithm
Checksum algorithm used. See
zfs(8) for more
information on checksum algorithms available.
cksum_byteswap
Whether or not the data is byteswapped.
bad_ranges
[start, end) pairs of corruption offsets. Offsets are
always aligned on a 64-bit boundary, and can include some gaps of
non-corruption. (See bad_ranges_min_gap)
bad_ranges_min_gap
In order to bound the size of the bad_ranges
array, gaps of non-corruption less than or equal to bad_ranges_min_gap
bytes have been merged with adjacent corruption. Always at least 8 bytes,
since corruption is detected on a 64-bit word basis.
bad_range_sets
This array has one element per range in
bad_ranges. Each element contains the count of bits in that range which
were clear in the good data and set in the bad data.
bad_range_clears
This array has one element per range in
bad_ranges. Each element contains the count of bits for that range
which were set in the good data and clear in the bad data.
bad_set_bits
If this field exists, it is an array of: (bad data &
~(good data)); that is, the bits set in the bad data which are cleared in the
good data. Each element corresponds a byte whose offset is in a range in
bad_ranges, and the array is ordered by offset. Thus, the first element
is the first byte in the first bad_ranges range, and the last element
is the last byte in the last bad_ranges range.
bad_cleared_bits
Like bad_set_bits, but contains: (good data &
~(bad data)); that is, the bits set in the good data which are cleared in the
bad data.
bad_set_histogram
If this field exists, it is an array of counters. Each
entry counts bits set in a particular bit of a big-endian uint64 type. The
first entry counts bits set in the high-order bit of the first byte, the 9th
byte, etc, and the last entry counts bits set of the low-order bit of the 8th
byte, the 16th byte, etc. This information is useful for observing a stuck bit
in a parallel data path, such as IDE or parallel SCSI.
bad_cleared_histogram
If this field exists, it is an array of counters. Each
entry counts bit clears in a particular bit of a big-endian uint64 type. The
first entry counts bits clears of the high-order bit of the first byte, the
9th byte, etc, and the last entry counts clears of the low-order bit of the
8th byte, the 16th byte, etc. This information is useful for observing a stuck
bit in a parallel data path, such as IDE or parallel SCSI.