5 .\" The contents of this file are subject to the terms of the
6 .\" Common Development and Distribution License (the "License").
7 .\" You may not use this file except in compliance with the License.
9 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 .\" or http://www.opensolaris.org/os/licensing.
11 .\" See the License for the specific language governing permissions
12 .\" and limitations under the License.
14 .\" When distributing Covered Code, include this CDDL HEADER in each
15 .\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 .\" If applicable, add the following below this CDDL HEADER, with the
17 .\" fields enclosed by brackets "[]" replaced with your own identifying
18 .\" information: Portions Copyright [yyyy] [name of copyright owner]
23 .\" Copyright 2013 Darik Horn <dajhorn@vanadac.com>. All rights reserved.
25 .TH zhack 1 "2013 MAR 16" "ZFS on Linux" "User Commands"
27 .BR zhack " \- libzpool debugging tool"
29 This utility pokes configuration changes directly into a ZFS pool,
30 which is dangerous and can cause data corruption.
33 .BI "zhack [\-c " "cachefile" "] [\-d " "dir" "] <" "subcommand" "> [" "arguments" "]"
36 .BI "\-c" " cachefile"
38 Read the \fIpool\fR configuration from the \fIcachefile\fR, which is
39 /etc/zfs/zpool.cache by default.
43 Search for \fIpool\fR members in the \fIdir\fR path. Can be specified
47 .BI "feature stat " "pool"
51 .BI "feature enable [\-d " "description" "] [\-r] " "pool guid"
53 Add a new feature to \fIpool\fR that is uniquely identified by
54 \fIguid\fR, which is specified in the same form as a zfs(8) user
57 The \fIdescription\fR is a short human readable explanation of the new
60 The \fB\-r\fR switch indicates that \fIpool\fR can be safely opened
61 in read-only mode by a system that does not have the \fIguid\fR
64 .BI "feature ref [\-d|\-m] " "pool guid"
66 Increment the reference count of the \fIguid\fR feature in \fIpool\fR.
68 The \fB\-d\fR switch decrements the reference count of the \fIguid\fR
69 feature in \fIpool\fR.
71 The \fB\-m\fR switch indicates that the \fIguid\fR feature is now
72 required to read the pool MOS.
76 # zhack feature stat tank
79 org.illumos:lz4_compress = 0
81 com.delphix:async_destroy = 0
82 com.delphix:empty_bpobj = 0
84 com.delphix:async_destroy = Destroy filesystems asynchronously.
85 com.delphix:empty_bpobj = Snapshots use less space.
86 org.illumos:lz4_compress = LZ4 compression algorithm support.
88 # zhack feature enable -d 'Predict future disk failures.' \\
89 tank com.example:clairvoyance
91 # zhack feature ref tank com.example:clairvoyance
93 This man page was written by Darik Horn <dajhorn@vanadac.com>.
98 .BR zpool-features (5),