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 'vzdump' is a utility to make consistent backups of running guest
  29 systems. It basically creates an archive of the guest private area,
  30 which also includes the guest configuration files. 'vzdump' currently
  31 supports LXC containers and QemuServer VMs. There are several ways to
  32 provide consistency (option `mode`), depending on the guest type.
  33
  34 .Backup `mode` for VMs:
  35
  36 `stop` mode::
  37
  38 This first performns a clean shutdown of the VM to make sure it is
  39 stopped. It then starts the VM in suspended mode and uses the qemu
  40 backup feature to dump all data. If the VM was running, we start
  41 (resume) it immediately after starting the qemu backup task. This
  42 keeps the downtime as low as possible.
  43
  44 `suspend` mode::
  45
  46 This mode does not really make sense for qemu. Please use snapshot
  47 mode instead.
  48
  49 `snapshot` mode::
  50
  51 This mode simply starts a qemu live backup task. If the guest agent
  52 is enabled (`agent: 1`) and running, it calls 'guest-fsfreeze-freeze'
  53 and 'guest-fsfreeze-thaw' to improve consistency.
  54
  55 A technical overview of the Proxmox VE live backup for QemuServer can
  56 be found online
  57 https://git.proxmox.com/?p=pve-qemu-kvm.git;a=blob;f=backup.txt[here].
  58
  59 NOTE: Qemu backup provides snapshots on any storage type. It does
  60 not require that the underlying storage supports snapshots.
  61
  62
  63 .Backup `mode` for Containers:
  64
  65 `stop` mode::
  66
  67 Stop the container for the duration of the backup. This potentially results in
  68 a very long downtime.
  69
  70 `suspend` mode::
  71
  72 This mode uses rsync to copy the container data to a temporary
  73 location (see option `--tmpdir`). Then the container is suspended and a second
  74 rsync copies changed files. After that, the container is started (resumed)
  75 again. This results in minimal downtime, but needs additional space
  76 to hold the container copy.
  77 +
  78 When the container is on a local filesystem and the target storage of the backup
  79 is an NFS server, you should set `--tmpdir` to reside on a local filesystem too,
  80 as this will result in a many fold performance improvement.
  81 Use of a local `tmpdir` is also required if you want to backup a local container
  82 using ACLs in suspend mode if the backup storage is an NFS server.
  83
  84 `snapshot` mode::
  85
  86 This mode uses the snapshotting facilities of the underlying
  87 storage. A snapshot will be made of the container volume, and the
  88 snapshot content will be archived in a tar file.
  89
  90
  91 Backup File Names
  92 -----------------
  93
  94 Newer versions of vzdump encode the guest type and the
  95 backup time into the filename, for example
  96
  97  vzdump-lxc-105-2009_10_09-11_04_43.tar
  98
  99 That way it is possible to store several backup in the same
 100 directory. The parameter `maxfiles` can be used to specify the
 101 maximum number of backups to keep.
 102
 103 Restore
 104 -------
 105
 106 The resulting archive files can be restored with the following programs.
 107
 108
 109 `pct restore`:: Container restore utility
 110
 111 `qmrestore`:: QemuServer restore utility
 112
 113 For details see the corresponding manual pages.
 114
 115 Configuration
 116 -------------
 117
 118 Global configuration is stored in '/etc/vzdump.conf'. The file uses a
 119 simple colon separated key/value format. Each line has the following
 120 format:
 121
 122  OPTION: value
 123
 124 Blank lines in the file are ignored, and lines starting with a '#'
 125 character are treated as comments and are also ignored. Values from
 126 this file are used as default, and can be overwritten on the command
 127 line.
 128
 129 We currently support the following options:
 130
 131 include::vzdump.conf.5-opts.adoc[]
 132
 133
 134 .Example 'vzdump.conf' Configuration
 135 ----
 136 tmpdir: /mnt/fast_local_disk
 137 storage: my_backup_storage
 138 mode: snapshot
 139 bwlimit: 10000
 140 ----
 141
 142 Hook Scripts
 143 ------------
 144
 145 You can specify a hook script with option `--script`. This script is
 146 called at various phases of the backup process, with parameters
 147 accordingly set. You can find an example in the documentation
 148 directory ('vzdump-hook-script.pl').
 149
 150 File Exclusions
 151 ---------------
 152
 153 NOTE: this option is only available for container backups.
 154
 155 'vzdump' skips the following files by default (disable with the option
 156 `--stdexcludes 0`)
 157
 158  /var/log/?*
 159  /tmp/?*
 160  /var/tmp/?*
 161  /var/run/?*pid
 162
 163 You can also manually specify (additional) exclude paths, for example:
 164
 165  # vzdump 777 --exclude-path /tmp/ --exclude-path '/var/foo*'
 166
 167 (only excludes tmp directories)
 168
 169 Configuration files are also stored inside the backup archive
 170 (in `./etc/vzdump/`) and will be correctly restored.
 171
 172 Examples
 173 --------
 174
 175 Simply dump guest 777 - no snapshot, just archive the guest private area and
 176 configuration files to the default dump directory (usually
 177 '/var/lib/vz/dump/').
 178
 179  # vzdump 777
 180
 181 Use rsync and suspend/resume to create a snapshot (minimal downtime).
 182
 183  # vzdump 777 --mode suspend
 184
 185 Backup all guest systems and send notification mails to root and admin.
 186
 187  # vzdump --all --mode suspend --mailto root --mailto admin
 188
 189 Use snapshot mode (no downtime).
 190
 191  # vzdump 777 --dumpdir /mnt/backup --mode snapshot
 192
 193 Backup more than one guest (selectively)
 194
 195  # vzdump 101 102 103 --mailto root
 196
 197 Backup all guests excluding 101 and 102
 198
 199  # vzdump --mode suspend --exclude 101,102
 200
 201 Restore a container to a new CT 600
 202
 203  # pct restore 600 /mnt/backup/vzdump-lxc-777.tar
 204
 205 Restore a QemuServer VM to VM 601
 206
 207  # qmrestore /mnt/backup/vzdump-qemu-888.vma 601
 208
 209 Clone an existing container 101 to a new container 300 with a 4GB root
 210 file system, using pipes
 211
 212  # vzdump 101 --stdout | pct restore --rootfs 4 300 -
 213
 214
 215 ifdef::manvolnum[]
 216 include::pve-copyright.adoc[]
 217 endif::manvolnum[]
 218