vzdump.adoc

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