4 include::attributes.txt[]
9 vzdump - Backup Utility for VMs and Containers
15 include::vzdump.1-synopsis.adoc[]
25 include::attributes.txt[]
28 Backups are a requirements for any sensible IT deployment, and {pve}
29 provides a fully integrated solution, using the capabilities of each
30 storage and each guest system type. This allows the system
31 administrator to fine tune via the `mode` option between consistency
32 of the backups and downtime of the guest system.
34 {pve} backups are always full backups - containing the VM/CT
35 configuration and all data. Backups can be started via the GUI or via
36 the `vzdump` command line tool.
40 Before a backup can run, a backup storage must be defined. Refer to
41 the Storage documentation on how to add a storage. A backup storage
42 must be a file level storage, as backups are stored as regular files.
43 In most situations, using a NFS server is a good way to store backups.
44 You can save those backups later to a tape drive, for off-site
49 Backup jobs can be scheduled so that they are executed automatically
50 on specific days and times, for selectable nodes and guest systems.
51 Configuration of scheduled backups is done at the Datacenter level in
52 the GUI, which will generate a cron entry in /etc/cron.d/vzdump.
57 There are several ways to provide consistency (option `mode`),
58 depending on the guest type.
60 .Backup modes for VMs:
64 This mode provides the highest consistency of the backup, at the cost
65 of a downtime in the VM operation. It works by executing an orderly
66 shutdown of the VM, and then runs a background Qemu process to backup
67 the VM data. After the backup is complete, the Qemu process resumes
68 the VM to full operation mode if it was previously running.
72 This mode is provided for compatibility reason, and suspends the VM
73 before calling the `snapshot` mode. Since suspending the VM results in
74 a longer downtime and does not necessarily improve the data
75 consistency, the use of the `snapshot` mode is recommended instead.
79 This mode provides the lowest operation downtime, at the cost of a
80 small inconstancy risk. It works by performing a Proxmox VE live
81 backup, in which data blocks are copied while the VM is running. If the
82 guest agent is enabled (`agent: 1`) and running, it calls
83 'guest-fsfreeze-freeze' and 'guest-fsfreeze-thaw' to improve
86 A technical overview of the Proxmox VE live backup for QemuServer can
88 https://git.proxmox.com/?p=pve-qemu-kvm.git;a=blob;f=backup.txt[here].
90 NOTE: Proxmox VE live backup provides snapshot-like semantics on any
91 storage type. It does not require that the underlying storage supports
94 .Backup modes for Containers:
98 Stop the container for the duration of the backup. This potentially
99 results in a very long downtime.
103 This mode uses rsync to copy the container data to a temporary
104 location (see option `--tmpdir`). Then the container is suspended and
105 a second rsync copies changed files. After that, the container is
106 started (resumed) again. This results in minimal downtime, but needs
107 additional space to hold the container copy.
109 When the container is on a local filesystem and the target storage of
110 the backup is an NFS server, you should set `--tmpdir` to reside on a
111 local filesystem too, as this will result in a many fold performance
112 improvement. Use of a local `tmpdir` is also required if you want to
113 backup a local container using ACLs in suspend mode if the backup
114 storage is an NFS server.
118 This mode uses the snapshotting facilities of the underlying
119 storage. First, the container will be suspended to ensure data consistency.
120 A temporary snapshot of the container's volumes will be made and the
121 snapshot content will be archived in a tar file. Finally, the temporary
122 snapshot is deleted again.
124 NOTE: `snapshot` mode requires that all backed up volumes are on a storage that
125 supports snapshots. Using the `backup=no` mountpoint option individual volumes
126 can be excluded from the backup (and thus this requirement).
128 NOTE: bind and device mountpoints are skipped during backup operations, like
129 volume mountpoints with the backup option disabled.
135 Newer versions of vzdump encode the guest type and the
136 backup time into the filename, for example
138 vzdump-lxc-105-2009_10_09-11_04_43.tar
140 That way it is possible to store several backup in the same
141 directory. The parameter `maxfiles` can be used to specify the
142 maximum number of backups to keep.
147 The resulting archive files can be restored with the following programs.
150 `pct restore`:: Container restore utility
152 `qmrestore`:: QemuServer restore utility
154 For details see the corresponding manual pages.
159 Global configuration is stored in '/etc/vzdump.conf'. The file uses a
160 simple colon separated key/value format. Each line has the following
165 Blank lines in the file are ignored, and lines starting with a '#'
166 character are treated as comments and are also ignored. Values from
167 this file are used as default, and can be overwritten on the command
170 We currently support the following options:
172 include::vzdump.conf.5-opts.adoc[]
175 .Example 'vzdump.conf' Configuration
177 tmpdir: /mnt/fast_local_disk
178 storage: my_backup_storage
186 You can specify a hook script with option `--script`. This script is
187 called at various phases of the backup process, with parameters
188 accordingly set. You can find an example in the documentation
189 directory ('vzdump-hook-script.pl').
194 NOTE: this option is only available for container backups.
196 'vzdump' skips the following files by default (disable with the option
203 You can also manually specify (additional) exclude paths, for example:
205 # vzdump 777 --exclude-path /tmp/ --exclude-path '/var/foo*'
207 (only excludes tmp directories)
209 Configuration files are also stored inside the backup archive
210 (in `./etc/vzdump/`) and will be correctly restored.
215 Simply dump guest 777 - no snapshot, just archive the guest private area and
216 configuration files to the default dump directory (usually
217 '/var/lib/vz/dump/').
221 Use rsync and suspend/resume to create a snapshot (minimal downtime).
223 # vzdump 777 --mode suspend
225 Backup all guest systems and send notification mails to root and admin.
227 # vzdump --all --mode suspend --mailto root --mailto admin
229 Use snapshot mode (no downtime) and non-default dump directory.
231 # vzdump 777 --dumpdir /mnt/backup --mode snapshot
233 Backup more than one guest (selectively)
235 # vzdump 101 102 103 --mailto root
237 Backup all guests excluding 101 and 102
239 # vzdump --mode suspend --exclude 101,102
241 Restore a container to a new CT 600
243 # pct restore 600 /mnt/backup/vzdump-lxc-777.tar
245 Restore a QemuServer VM to VM 601
247 # qmrestore /mnt/backup/vzdump-qemu-888.vma 601
249 Clone an existing container 101 to a new container 300 with a 4GB root
250 file system, using pipes
252 # vzdump 101 --stdout | pct restore --rootfs 4 300 -
256 include::pve-copyright.adoc[]