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1 | acd935ef | bellard | @example |
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2 | acd935ef | bellard | @c man begin SYNOPSIS |
3 | acd935ef | bellard | usage: qemu-img command [command options] |
4 | acd935ef | bellard | @c man end |
5 | acd935ef | bellard | @end example |
6 | acd935ef | bellard | |
7 | acd935ef | bellard | @c man begin OPTIONS |
8 | acd935ef | bellard | |
9 | acd935ef | bellard | The following commands are supported: |
10 | 153859be | Stuart Brady | |
11 | 153859be | Stuart Brady | @include qemu-img-cmds.texi |
12 | acd935ef | bellard | |
13 | acd935ef | bellard | Command parameters: |
14 | acd935ef | bellard | @table @var |
15 | acd935ef | bellard | @item filename |
16 | acd935ef | bellard | is a disk image filename |
17 | 5fafdf24 | ths | @item fmt |
18 | f932c040 | Kevin Wolf | is the disk image format. It is guessed automatically in most cases. See below |
19 | f932c040 | Kevin Wolf | for a description of the supported disk formats. |
20 | acd935ef | bellard | |
21 | 5fafdf24 | ths | @item size |
22 | eff44266 | Kevin Wolf | is the disk image size in bytes. Optional suffixes @code{k} or @code{K} |
23 | eff44266 | Kevin Wolf | (kilobyte, 1024) @code{M} (megabyte, 1024k) and @code{G} (gigabyte, 1024M) |
24 | eff44266 | Kevin Wolf | and T (terabyte, 1024G) are supported. @code{b} is ignored. |
25 | acd935ef | bellard | |
26 | acd935ef | bellard | @item output_filename |
27 | 5fafdf24 | ths | is the destination disk image filename |
28 | acd935ef | bellard | |
29 | acd935ef | bellard | @item output_fmt |
30 | acd935ef | bellard | is the destination format |
31 | eff44266 | Kevin Wolf | @item options |
32 | eff44266 | Kevin Wolf | is a comma separated list of format specific options in a |
33 | eff44266 | Kevin Wolf | name=value format. Use @code{-o ?} for an overview of the options supported |
34 | 3e032364 | Kevin Wolf | by the used format or see the format descriptions below for details. |
35 | eff44266 | Kevin Wolf | |
36 | acd935ef | bellard | |
37 | acd935ef | bellard | @item -c |
38 | acd935ef | bellard | indicates that target image must be compressed (qcow format only) |
39 | d2c639d6 | blueswir1 | @item -h |
40 | d2c639d6 | blueswir1 | with or without a command shows help and lists the supported formats |
41 | d2c639d6 | blueswir1 | @end table |
42 | d2c639d6 | blueswir1 | |
43 | d2c639d6 | blueswir1 | Parameters to snapshot subcommand: |
44 | d2c639d6 | blueswir1 | |
45 | d2c639d6 | blueswir1 | @table @option |
46 | d2c639d6 | blueswir1 | |
47 | d2c639d6 | blueswir1 | @item snapshot |
48 | d2c639d6 | blueswir1 | is the name of the snapshot to create, apply or delete |
49 | d2c639d6 | blueswir1 | @item -a |
50 | d2c639d6 | blueswir1 | applies a snapshot (revert disk to saved state) |
51 | d2c639d6 | blueswir1 | @item -c |
52 | d2c639d6 | blueswir1 | creates a snapshot |
53 | d2c639d6 | blueswir1 | @item -d |
54 | d2c639d6 | blueswir1 | deletes a snapshot |
55 | d2c639d6 | blueswir1 | @item -l |
56 | d2c639d6 | blueswir1 | lists all snapshots in the given image |
57 | acd935ef | bellard | @end table |
58 | acd935ef | bellard | |
59 | acd935ef | bellard | Command description: |
60 | acd935ef | bellard | |
61 | acd935ef | bellard | @table @option |
62 | e6184690 | Kevin Wolf | @item check [-f @var{fmt}] @var{filename} |
63 | e6184690 | Kevin Wolf | |
64 | e6184690 | Kevin Wolf | Perform a consistency check on the disk image @var{filename}. |
65 | e6184690 | Kevin Wolf | |
66 | e6184690 | Kevin Wolf | Only the formats @code{qcow2}, @code{qed} and @code{vdi} support |
67 | e6184690 | Kevin Wolf | consistency checks. |
68 | e6184690 | Kevin Wolf | |
69 | 8063d0fe | Kevin Wolf | @item create [-f @var{fmt}] [-o @var{options}] @var{filename} [@var{size}] |
70 | acd935ef | bellard | |
71 | acd935ef | bellard | Create the new disk image @var{filename} of size @var{size} and format |
72 | 8063d0fe | Kevin Wolf | @var{fmt}. Depending on the file format, you can add one or more @var{options} |
73 | 8063d0fe | Kevin Wolf | that enable additional features of this format. |
74 | acd935ef | bellard | |
75 | 8063d0fe | Kevin Wolf | If the option @var{backing_file} is specified, then the image will record |
76 | 8063d0fe | Kevin Wolf | only the differences from @var{backing_file}. No size needs to be specified in |
77 | 8063d0fe | Kevin Wolf | this case. @var{backing_file} will never be modified unless you use the |
78 | 8063d0fe | Kevin Wolf | @code{commit} monitor command (or qemu-img commit). |
79 | acd935ef | bellard | |
80 | eff44266 | Kevin Wolf | The size can also be specified using the @var{size} option with @code{-o}, |
81 | eff44266 | Kevin Wolf | it doesn't need to be specified separately in this case. |
82 | eff44266 | Kevin Wolf | |
83 | acd935ef | bellard | @item commit [-f @var{fmt}] @var{filename} |
84 | acd935ef | bellard | |
85 | acd935ef | bellard | Commit the changes recorded in @var{filename} in its base image. |
86 | acd935ef | bellard | |
87 | 51ef6727 | edison | @item convert [-c] [-f @var{fmt}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_name}] @var{filename} [@var{filename2} [...]] @var{output_filename} |
88 | acd935ef | bellard | |
89 | 51ef6727 | edison | Convert the disk image @var{filename} or a snapshot @var{snapshot_name} to disk image @var{output_filename} |
90 | eff44266 | Kevin Wolf | using format @var{output_fmt}. It can be optionally compressed (@code{-c} |
91 | eff44266 | Kevin Wolf | option) or use any format specific options like encryption (@code{-o} option). |
92 | acd935ef | bellard | |
93 | 8063d0fe | Kevin Wolf | Only the formats @code{qcow} and @code{qcow2} support compression. The |
94 | acd935ef | bellard | compression is read-only. It means that if a compressed sector is |
95 | acd935ef | bellard | rewritten, then it is rewritten as uncompressed data. |
96 | acd935ef | bellard | |
97 | acd935ef | bellard | Image conversion is also useful to get smaller image when using a |
98 | acd935ef | bellard | growable format such as @code{qcow} or @code{cow}: the empty sectors |
99 | acd935ef | bellard | are detected and suppressed from the destination image. |
100 | acd935ef | bellard | |
101 | 8063d0fe | Kevin Wolf | You can use the @var{backing_file} option to force the output image to be |
102 | 8063d0fe | Kevin Wolf | created as a copy on write image of the specified base image; the |
103 | 8063d0fe | Kevin Wolf | @var{backing_file} should have the same content as the input's base image, |
104 | 8063d0fe | Kevin Wolf | however the path, image format, etc may differ. |
105 | 8063d0fe | Kevin Wolf | |
106 | acd935ef | bellard | @item info [-f @var{fmt}] @var{filename} |
107 | acd935ef | bellard | |
108 | acd935ef | bellard | Give information about the disk image @var{filename}. Use it in |
109 | acd935ef | bellard | particular to know the size reserved on disk which can be different |
110 | 19d36792 | bellard | from the displayed size. If VM snapshots are stored in the disk image, |
111 | 19d36792 | bellard | they are displayed too. |
112 | d2c639d6 | blueswir1 | |
113 | d2c639d6 | blueswir1 | @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot} ] @var{filename} |
114 | d2c639d6 | blueswir1 | |
115 | d2c639d6 | blueswir1 | List, apply, create or delete snapshots in image @var{filename}. |
116 | ae6b0ed6 | Stefan Hajnoczi | |
117 | e6184690 | Kevin Wolf | @item rebase [-f @var{fmt}] [-u] -b @var{backing_file} [-F @var{backing_fmt}] @var{filename} |
118 | e6184690 | Kevin Wolf | |
119 | e6184690 | Kevin Wolf | Changes the backing file of an image. Only the formats @code{qcow2} and |
120 | e6184690 | Kevin Wolf | @code{qed} support changing the backing file. |
121 | e6184690 | Kevin Wolf | |
122 | e6184690 | Kevin Wolf | The backing file is changed to @var{backing_file} and (if the image format of |
123 | e6184690 | Kevin Wolf | @var{filename} supports this) the backing file format is changed to |
124 | e6184690 | Kevin Wolf | @var{backing_fmt}. |
125 | e6184690 | Kevin Wolf | |
126 | e6184690 | Kevin Wolf | There are two different modes in which @code{rebase} can operate: |
127 | e6184690 | Kevin Wolf | @table @option |
128 | e6184690 | Kevin Wolf | @item Safe mode |
129 | e6184690 | Kevin Wolf | This is the default mode and performs a real rebase operation. The new backing |
130 | e6184690 | Kevin Wolf | file may differ from the old one and qemu-img rebase will take care of keeping |
131 | e6184690 | Kevin Wolf | the guest-visible content of @var{filename} unchanged. |
132 | e6184690 | Kevin Wolf | |
133 | e6184690 | Kevin Wolf | In order to achieve this, any clusters that differ between @var{backing_file} |
134 | e6184690 | Kevin Wolf | and the old backing file of @var{filename} are merged into @var{filename} |
135 | e6184690 | Kevin Wolf | before actually changing the backing file. |
136 | e6184690 | Kevin Wolf | |
137 | e6184690 | Kevin Wolf | Note that the safe mode is an expensive operation, comparable to converting |
138 | e6184690 | Kevin Wolf | an image. It only works if the old backing file still exists. |
139 | e6184690 | Kevin Wolf | |
140 | e6184690 | Kevin Wolf | @item Unsafe mode |
141 | e6184690 | Kevin Wolf | qemu-img uses the unsafe mode if @code{-u} is specified. In this mode, only the |
142 | e6184690 | Kevin Wolf | backing file name and format of @var{filename} is changed without any checks |
143 | e6184690 | Kevin Wolf | on the file contents. The user must take care of specifying the correct new |
144 | e6184690 | Kevin Wolf | backing file, or the guest-visible content of the image will be corrupted. |
145 | e6184690 | Kevin Wolf | |
146 | e6184690 | Kevin Wolf | This mode is useful for renaming or moving the backing file to somewhere else. |
147 | e6184690 | Kevin Wolf | It can be used without an accessible old backing file, i.e. you can use it to |
148 | e6184690 | Kevin Wolf | fix an image whose backing file has already been moved/renamed. |
149 | e6184690 | Kevin Wolf | @end table |
150 | e6184690 | Kevin Wolf | |
151 | ae6b0ed6 | Stefan Hajnoczi | @item resize @var{filename} [+ | -]@var{size} |
152 | ae6b0ed6 | Stefan Hajnoczi | |
153 | ae6b0ed6 | Stefan Hajnoczi | Change the disk image as if it had been created with @var{size}. |
154 | ae6b0ed6 | Stefan Hajnoczi | |
155 | ae6b0ed6 | Stefan Hajnoczi | Before using this command to shrink a disk image, you MUST use file system and |
156 | ae6b0ed6 | Stefan Hajnoczi | partitioning tools inside the VM to reduce allocated file systems and partition |
157 | ae6b0ed6 | Stefan Hajnoczi | sizes accordingly. Failure to do so will result in data loss! |
158 | ae6b0ed6 | Stefan Hajnoczi | |
159 | ae6b0ed6 | Stefan Hajnoczi | After using this command to grow a disk image, you must use file system and |
160 | ae6b0ed6 | Stefan Hajnoczi | partitioning tools inside the VM to actually begin using the new space on the |
161 | ae6b0ed6 | Stefan Hajnoczi | device. |
162 | acd935ef | bellard | @end table |
163 | acd935ef | bellard | |
164 | f932c040 | Kevin Wolf | Supported image file formats: |
165 | f932c040 | Kevin Wolf | |
166 | f932c040 | Kevin Wolf | @table @option |
167 | f932c040 | Kevin Wolf | @item raw |
168 | f932c040 | Kevin Wolf | |
169 | f932c040 | Kevin Wolf | Raw disk image format (default). This format has the advantage of |
170 | f932c040 | Kevin Wolf | being simple and easily exportable to all other emulators. If your |
171 | f932c040 | Kevin Wolf | file system supports @emph{holes} (for example in ext2 or ext3 on |
172 | f932c040 | Kevin Wolf | Linux or NTFS on Windows), then only the written sectors will reserve |
173 | f932c040 | Kevin Wolf | space. Use @code{qemu-img info} to know the real size used by the |
174 | f932c040 | Kevin Wolf | image or @code{ls -ls} on Unix/Linux. |
175 | f932c040 | Kevin Wolf | |
176 | f932c040 | Kevin Wolf | @item host_device |
177 | f932c040 | Kevin Wolf | |
178 | f932c040 | Kevin Wolf | Host device format. This format should be used instead of raw when |
179 | f932c040 | Kevin Wolf | converting to block devices or other devices where "holes" are not |
180 | f932c040 | Kevin Wolf | supported. |
181 | f932c040 | Kevin Wolf | |
182 | f932c040 | Kevin Wolf | @item qcow2 |
183 | f932c040 | Kevin Wolf | QEMU image format, the most versatile format. Use it to have smaller |
184 | f932c040 | Kevin Wolf | images (useful if your filesystem does not supports holes, for example |
185 | f932c040 | Kevin Wolf | on Windows), optional AES encryption, zlib based compression and |
186 | f932c040 | Kevin Wolf | support of multiple VM snapshots. |
187 | 8063d0fe | Kevin Wolf | |
188 | 3e032364 | Kevin Wolf | Supported options: |
189 | 3e032364 | Kevin Wolf | @table @code |
190 | 3e032364 | Kevin Wolf | @item backing_file |
191 | 3e032364 | Kevin Wolf | File name of a base image (see @option{create} subcommand) |
192 | 3e032364 | Kevin Wolf | @item backing_fmt |
193 | 3e032364 | Kevin Wolf | Image format of the base image |
194 | 3e032364 | Kevin Wolf | @item encryption |
195 | 3e032364 | Kevin Wolf | If this option is set to @code{on}, the image is encrypted. |
196 | 3e032364 | Kevin Wolf | |
197 | 8063d0fe | Kevin Wolf | Encryption uses the AES format which is very secure (128 bit keys). Use |
198 | 8063d0fe | Kevin Wolf | a long password (16 characters) to get maximum protection. |
199 | 3e032364 | Kevin Wolf | |
200 | 3e032364 | Kevin Wolf | @item cluster_size |
201 | 3e032364 | Kevin Wolf | Changes the qcow2 cluster size (must be between 512 and 2M). Smaller cluster |
202 | 3e032364 | Kevin Wolf | sizes can improve the image file size whereas larger cluster sizes generally |
203 | 3e032364 | Kevin Wolf | provide better performance. |
204 | 3e032364 | Kevin Wolf | |
205 | 3e032364 | Kevin Wolf | @item preallocation |
206 | 3e032364 | Kevin Wolf | Preallocation mode (allowed values: off, metadata). An image with preallocated |
207 | 3e032364 | Kevin Wolf | metadata is initially larger but can improve performance when the image needs |
208 | 3e032364 | Kevin Wolf | to grow. |
209 | 3e032364 | Kevin Wolf | |
210 | 3e032364 | Kevin Wolf | @end table |
211 | 3e032364 | Kevin Wolf | |
212 | 3e032364 | Kevin Wolf | |
213 | f932c040 | Kevin Wolf | @item qcow |
214 | f932c040 | Kevin Wolf | Old QEMU image format. Left for compatibility. |
215 | 3e032364 | Kevin Wolf | |
216 | 3e032364 | Kevin Wolf | Supported options: |
217 | 3e032364 | Kevin Wolf | @table @code |
218 | 3e032364 | Kevin Wolf | @item backing_file |
219 | 3e032364 | Kevin Wolf | File name of a base image (see @option{create} subcommand) |
220 | 3e032364 | Kevin Wolf | @item encryption |
221 | 3e032364 | Kevin Wolf | If this option is set to @code{on}, the image is encrypted. |
222 | 3e032364 | Kevin Wolf | @end table |
223 | 3e032364 | Kevin Wolf | |
224 | f932c040 | Kevin Wolf | @item cow |
225 | f932c040 | Kevin Wolf | User Mode Linux Copy On Write image format. Used to be the only growable |
226 | f932c040 | Kevin Wolf | image format in QEMU. It is supported only for compatibility with |
227 | f932c040 | Kevin Wolf | previous versions. It does not work on win32. |
228 | f932c040 | Kevin Wolf | @item vdi |
229 | f932c040 | Kevin Wolf | VirtualBox 1.1 compatible image format. |
230 | f932c040 | Kevin Wolf | @item vmdk |
231 | f932c040 | Kevin Wolf | VMware 3 and 4 compatible image format. |
232 | 3e032364 | Kevin Wolf | |
233 | 3e032364 | Kevin Wolf | Supported options: |
234 | 3e032364 | Kevin Wolf | @table @code |
235 | 3e032364 | Kevin Wolf | @item backing_fmt |
236 | 3e032364 | Kevin Wolf | Image format of the base image |
237 | 3e032364 | Kevin Wolf | @item compat6 |
238 | 3e032364 | Kevin Wolf | Create a VMDK version 6 image (instead of version 4) |
239 | 3e032364 | Kevin Wolf | @end table |
240 | 3e032364 | Kevin Wolf | |
241 | 3e032364 | Kevin Wolf | @item vpc |
242 | 3e032364 | Kevin Wolf | VirtualPC compatible image format (VHD). |
243 | 3e032364 | Kevin Wolf | |
244 | f932c040 | Kevin Wolf | @item cloop |
245 | f932c040 | Kevin Wolf | Linux Compressed Loop image, useful only to reuse directly compressed |
246 | f932c040 | Kevin Wolf | CD-ROM images present for example in the Knoppix CD-ROMs. |
247 | f932c040 | Kevin Wolf | @end table |
248 | f932c040 | Kevin Wolf | |
249 | f932c040 | Kevin Wolf | |
250 | acd935ef | bellard | @c man end |
251 | acd935ef | bellard | |
252 | acd935ef | bellard | @ignore |
253 | acd935ef | bellard | |
254 | acd935ef | bellard | @setfilename qemu-img |
255 | acd935ef | bellard | @settitle QEMU disk image utility |
256 | acd935ef | bellard | |
257 | acd935ef | bellard | @c man begin SEEALSO |
258 | acd935ef | bellard | The HTML documentation of QEMU for more precise information and Linux |
259 | acd935ef | bellard | user mode emulator invocation. |
260 | acd935ef | bellard | @c man end |
261 | acd935ef | bellard | |
262 | acd935ef | bellard | @c man begin AUTHOR |
263 | acd935ef | bellard | Fabrice Bellard |
264 | acd935ef | bellard | @c man end |
265 | acd935ef | bellard | |
266 | acd935ef | bellard | @end ignore |