Section: User Commands (1)
Updated: 2013 MAR 16
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zhack - libzpool debugging tool
This utility pokes configuration changes directly into a ZFS pool,
which is dangerous and can cause data corruption.
zhack [-c cachefile] [-d dir] <subcommand> [arguments]
- Read the pool configuration from the cachefile, which is
/etc/zfs/zpool.cache by default.
- Search for pool members in the dir path. Can be specified
more than once.
feature stat pool
List feature flags.
feature enable [-d description] [-r] pool guid
Add a new feature to pool that is uniquely identified by
guid, which is specified in the same form as a zfs(8) user
The description is a short human readable explanation of the new
The -r switch indicates that pool can be safely opened
in read-only mode by a system that does not have the guid
feature ref [-d|-m] pool guid
Increment the reference count of the guid feature in pool.
The -d switch decrements the reference count of the guid
feature in pool.
The -m switch indicates that the guid feature is now
required to read the pool MOS.
# zhack feature stat tank
org.illumos:lz4_compress = 0
com.delphix:async_destroy = 0
com.delphix:empty_bpobj = 0
com.delphix:async_destroy = Destroy filesystems asynchronously.
com.delphix:empty_bpobj = Snapshots use less space.
org.illumos:lz4_compress = LZ4 compression algorithm support.
# zhack feature enable -d 'Predict future disk failures.' \
# zhack feature ref tank com.example:clairvoyance
This man page was written by Darik Horn <email@example.com>.