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1 | [[chapter_vzdump]] | |
2 | ifdef::manvolnum[] | |
3 | vzdump(1) | |
4 | ========= | |
5 | include::attributes.txt[] | |
6 | :pve-toplevel: | |
7 | ||
8 | NAME | |
9 | ---- | |
10 | ||
11 | vzdump - Backup Utility for VMs and Containers | |
12 | ||
13 | ||
14 | SYNOPSIS | |
15 | -------- | |
16 | ||
17 | include::vzdump.1-synopsis.adoc[] | |
18 | ||
19 | ||
20 | DESCRIPTION | |
21 | ----------- | |
22 | endif::manvolnum[] | |
23 | ifndef::manvolnum[] | |
24 | Backup and Restore | |
25 | ================== | |
26 | include::attributes.txt[] | |
27 | :pve-toplevel: | |
28 | endif::manvolnum[] | |
29 | ||
30 | Backups are a requirements for any sensible IT deployment, and {pve} | |
31 | provides a fully integrated solution, using the capabilities of each | |
32 | storage and each guest system type. This allows the system | |
33 | administrator to fine tune via the `mode` option between consistency | |
34 | of the backups and downtime of the guest system. | |
35 | ||
36 | {pve} backups are always full backups - containing the VM/CT | |
37 | configuration and all data. Backups can be started via the GUI or via | |
38 | the `vzdump` command line tool. | |
39 | ||
40 | .Backup Storage | |
41 | ||
42 | Before a backup can run, a backup storage must be defined. Refer to | |
43 | the Storage documentation on how to add a storage. A backup storage | |
44 | must be a file level storage, as backups are stored as regular files. | |
45 | In most situations, using a NFS server is a good way to store backups. | |
46 | You can save those backups later to a tape drive, for off-site | |
47 | archiving. | |
48 | ||
49 | .Scheduled Backup | |
50 | ||
51 | Backup jobs can be scheduled so that they are executed automatically | |
52 | on specific days and times, for selectable nodes and guest systems. | |
53 | Configuration of scheduled backups is done at the Datacenter level in | |
54 | the GUI, which will generate a cron entry in /etc/cron.d/vzdump. | |
55 | ||
56 | Backup modes | |
57 | ------------ | |
58 | ||
59 | There are several ways to provide consistency (option `mode`), | |
60 | depending on the guest type. | |
61 | ||
62 | .Backup modes for VMs: | |
63 | ||
64 | `stop` mode:: | |
65 | ||
66 | This mode provides the highest consistency of the backup, at the cost | |
67 | of a downtime in the VM operation. It works by executing an orderly | |
68 | shutdown of the VM, and then runs a background Qemu process to backup | |
69 | the VM data. After the backup is complete, the Qemu process resumes | |
70 | the VM to full operation mode if it was previously running. | |
71 | ||
72 | `suspend` mode:: | |
73 | ||
74 | This mode is provided for compatibility reason, and suspends the VM | |
75 | before calling the `snapshot` mode. Since suspending the VM results in | |
76 | a longer downtime and does not necessarily improve the data | |
77 | consistency, the use of the `snapshot` mode is recommended instead. | |
78 | ||
79 | `snapshot` mode:: | |
80 | ||
81 | This mode provides the lowest operation downtime, at the cost of a | |
82 | small inconstancy risk. It works by performing a Proxmox VE live | |
83 | backup, in which data blocks are copied while the VM is running. If the | |
84 | guest agent is enabled (`agent: 1`) and running, it calls | |
85 | `guest-fsfreeze-freeze` and `guest-fsfreeze-thaw` to improve | |
86 | consistency. | |
87 | ||
88 | A technical overview of the Proxmox VE live backup for QemuServer can | |
89 | be found online | |
90 | https://git.proxmox.com/?p=pve-qemu-kvm.git;a=blob;f=backup.txt[here]. | |
91 | ||
92 | NOTE: Proxmox VE live backup provides snapshot-like semantics on any | |
93 | storage type. It does not require that the underlying storage supports | |
94 | snapshots. | |
95 | ||
96 | .Backup modes for Containers: | |
97 | ||
98 | `stop` mode:: | |
99 | ||
100 | Stop the container for the duration of the backup. This potentially | |
101 | results in a very long downtime. | |
102 | ||
103 | `suspend` mode:: | |
104 | ||
105 | This mode uses rsync to copy the container data to a temporary | |
106 | location (see option `--tmpdir`). Then the container is suspended and | |
107 | a second rsync copies changed files. After that, the container is | |
108 | started (resumed) again. This results in minimal downtime, but needs | |
109 | additional space to hold the container copy. | |
110 | + | |
111 | When the container is on a local file system and the target storage of | |
112 | the backup is an NFS server, you should set `--tmpdir` to reside on a | |
113 | local file system too, as this will result in a many fold performance | |
114 | improvement. Use of a local `tmpdir` is also required if you want to | |
115 | backup a local container using ACLs in suspend mode if the backup | |
116 | storage is an NFS server. | |
117 | ||
118 | `snapshot` mode:: | |
119 | ||
120 | This mode uses the snapshotting facilities of the underlying | |
121 | storage. First, the container will be suspended to ensure data consistency. | |
122 | A temporary snapshot of the container's volumes will be made and the | |
123 | snapshot content will be archived in a tar file. Finally, the temporary | |
124 | snapshot is deleted again. | |
125 | ||
126 | NOTE: `snapshot` mode requires that all backed up volumes are on a storage that | |
127 | supports snapshots. Using the `backup=no` mount point option individual volumes | |
128 | can be excluded from the backup (and thus this requirement). | |
129 | ||
130 | NOTE: bind and device mount points are skipped during backup operations, like | |
131 | volume mount points with the backup option disabled. | |
132 | ||
133 | ||
134 | Backup File Names | |
135 | ----------------- | |
136 | ||
137 | Newer versions of vzdump encode the guest type and the | |
138 | backup time into the filename, for example | |
139 | ||
140 | vzdump-lxc-105-2009_10_09-11_04_43.tar | |
141 | ||
142 | That way it is possible to store several backup in the same | |
143 | directory. The parameter `maxfiles` can be used to specify the | |
144 | maximum number of backups to keep. | |
145 | ||
146 | Restore | |
147 | ------- | |
148 | ||
149 | The resulting archive files can be restored with the following programs. | |
150 | ||
151 | ||
152 | `pct restore`:: Container restore utility | |
153 | ||
154 | `qmrestore`:: QemuServer restore utility | |
155 | ||
156 | For details see the corresponding manual pages. | |
157 | ||
158 | Configuration | |
159 | ------------- | |
160 | ||
161 | Global configuration is stored in `/etc/vzdump.conf`. The file uses a | |
162 | simple colon separated key/value format. Each line has the following | |
163 | format: | |
164 | ||
165 | OPTION: value | |
166 | ||
167 | Blank lines in the file are ignored, and lines starting with a `#` | |
168 | character are treated as comments and are also ignored. Values from | |
169 | this file are used as default, and can be overwritten on the command | |
170 | line. | |
171 | ||
172 | We currently support the following options: | |
173 | ||
174 | include::vzdump.conf.5-opts.adoc[] | |
175 | ||
176 | ||
177 | .Example `vzdump.conf` Configuration | |
178 | ---- | |
179 | tmpdir: /mnt/fast_local_disk | |
180 | storage: my_backup_storage | |
181 | mode: snapshot | |
182 | bwlimit: 10000 | |
183 | ---- | |
184 | ||
185 | Hook Scripts | |
186 | ------------ | |
187 | ||
188 | You can specify a hook script with option `--script`. This script is | |
189 | called at various phases of the backup process, with parameters | |
190 | accordingly set. You can find an example in the documentation | |
191 | directory (`vzdump-hook-script.pl`). | |
192 | ||
193 | File Exclusions | |
194 | --------------- | |
195 | ||
196 | NOTE: this option is only available for container backups. | |
197 | ||
198 | `vzdump` skips the following files by default (disable with the option | |
199 | `--stdexcludes 0`) | |
200 | ||
201 | /tmp/?* | |
202 | /var/tmp/?* | |
203 | /var/run/?*pid | |
204 | ||
205 | You can also manually specify (additional) exclude paths, for example: | |
206 | ||
207 | # vzdump 777 --exclude-path /tmp/ --exclude-path '/var/foo*' | |
208 | ||
209 | (only excludes tmp directories) | |
210 | ||
211 | Configuration files are also stored inside the backup archive | |
212 | (in `./etc/vzdump/`) and will be correctly restored. | |
213 | ||
214 | Examples | |
215 | -------- | |
216 | ||
217 | Simply dump guest 777 - no snapshot, just archive the guest private area and | |
218 | configuration files to the default dump directory (usually | |
219 | `/var/lib/vz/dump/`). | |
220 | ||
221 | # vzdump 777 | |
222 | ||
223 | Use rsync and suspend/resume to create a snapshot (minimal downtime). | |
224 | ||
225 | # vzdump 777 --mode suspend | |
226 | ||
227 | Backup all guest systems and send notification mails to root and admin. | |
228 | ||
229 | # vzdump --all --mode suspend --mailto root --mailto admin | |
230 | ||
231 | Use snapshot mode (no downtime) and non-default dump directory. | |
232 | ||
233 | # vzdump 777 --dumpdir /mnt/backup --mode snapshot | |
234 | ||
235 | Backup more than one guest (selectively) | |
236 | ||
237 | # vzdump 101 102 103 --mailto root | |
238 | ||
239 | Backup all guests excluding 101 and 102 | |
240 | ||
241 | # vzdump --mode suspend --exclude 101,102 | |
242 | ||
243 | Restore a container to a new CT 600 | |
244 | ||
245 | # pct restore 600 /mnt/backup/vzdump-lxc-777.tar | |
246 | ||
247 | Restore a QemuServer VM to VM 601 | |
248 | ||
249 | # qmrestore /mnt/backup/vzdump-qemu-888.vma 601 | |
250 | ||
251 | Clone an existing container 101 to a new container 300 with a 4GB root | |
252 | file system, using pipes | |
253 | ||
254 | # vzdump 101 --stdout | pct restore --rootfs 4 300 - | |
255 | ||
256 | ||
257 | ifdef::manvolnum[] | |
258 | include::pve-copyright.adoc[] | |
259 | endif::manvolnum[] | |
260 |