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 guest during backup. This results in a very long downtime.
  68
  69 `suspend` mode::
  70
  71 This mode uses rsync to copy the container data to a temporary
  72 location (see option `--tmpdir`). Then the container is suspended and a second
  73 rsync copies changed files. After that, the container is started (resumed)
  74 again. This results in minimal downtime, but needs additional space
  75 to hold the container copy.
  76 +
  77 When the container is on a local filesystem and the target storage of the backup
  78 is an NFS server, you should set `--tmpdir` to reside on a local filesystem too,
  79 as this will result in a many fold performance improvement.
  80 Use of a local `tmpdir` is also required if you want to backup in `suspend`
  81 mode a local container using ACLs to an NFS server.
  82
  83 `snapshot` mode::
  84
  85 This mode uses the snapshotting facilities of the underlying
  86 storage. A snapshot will be made of the container volume, and the
  87 snapshot content will be archived in a tar file.
  88
  89
  90 Backup File Names
  91 -----------------
  92
  93 Newer versions of vzdump encode the virtual machine type and the
  94 backup time into the filename, for example
  95
  96  vzdump-lxc-105-2009_10_09-11_04_43.tar
  97
  98 That way it is possible to store several backup in the same
  99 directory. The parameter `maxfiles` can be used to specify the
 100 maximum number of backups to keep.
 101
 102 Restore
 103 -------
 104
 105 The resulting archive files can be restored with the following programs.
 106
 107
 108 `pct restore`:: Container restore utility
 109
 110 `qmrestore`:: QemuServer restore utility
 111
 112 For details see the corresponding manual pages.
 113
 114 Configuration
 115 -------------
 116
 117 Global configuration is stored in '/etc/vzdump.conf'. The file uses a
 118 simple colon separated key/value format. Each line has the following
 119 format:
 120
 121  OPTION: value
 122
 123 Blank lines in the file are ignored, and lines starting with a '#'
 124 character are treated as comments and are also ignored. Values from
 125 this file are used as default, and can be overwritten on the command
 126 line.
 127
 128 We currently support the following options:
 129
 130 include::vzdump.conf.5-opts.adoc[]
 131
 132
 133 .Example 'vzdump.conf' Configuration
 134 ----
 135 tmpdir: /mnt/fast_local_disk
 136 storage: my_backup_storage
 137 mode: snapshot
 138 bwlimit: 10000
 139 ----
 140
 141 Hook Scripts
 142 ------------
 143
 144 You can specify a hook script with option `--script`. This script is
 145 called at various phases of the backup process, with parameters
 146 accordingly set. You can find an example in the documentation
 147 directory ('vzdump-hook-script.pl').
 148
 149 File Exclusions
 150 ---------------
 151
 152 First, this option is only available for container backups. 'vzdump'
 153 skips the following files with option `--stdexcludes`
 154
 155  /var/log/?*
 156  /tmp/?*
 157  /var/tmp/?*
 158  /var/run/?*pid
 159
 160 Or you can manually specify exclude paths, for example:
 161
 162  # vzdump 777 --exclude-path /tmp/ --exclude-path '/var/foo*'
 163
 164 (only excludes tmp directories)
 165
 166 Configuration files are also stored inside the backup archive
 167 (`/etc/vzdump/`), and will be correctly restored.
 168
 169 Examples
 170 --------
 171
 172 Simply dump guest 777 - no snapshot, just archive the guest private area and
 173 configuration files to the default dump directory (usually
 174 '/var/liv//vz/dump/').
 175
 176  # vzdump 777
 177
 178 Use rsync and suspend/resume to create a snapshot (minimal downtime).
 179
 180  # vzdump 777 --mode suspend
 181
 182 Backup all guest systems and send notification mails to root and admin.
 183
 184  # vzdump --all --mode suspend --mailto root --mailto admin
 185
 186 Use snapshot mode (no downtime).
 187
 188  # vzdump 777 --dumpdir /mnt/backup --mode snapshot
 189
 190 Backup more than one guest (selectively)
 191
 192  # vzdump 101 102 103 --mailto root
 193
 194 Backup all guests excluding 101 and 102
 195
 196  # vzdump --mode suspend --exclude 101,102
 197
 198 Restore a container to a new CT 600
 199
 200  # pct restore 600 /mnt/backup/vzdump-lxc-777.tar
 201
 202 Restore a QemuServer VM to VM 601
 203
 204  # qmrestore /mnt/backup/vzdump-qemu-888.vma 601
 205
 206 Clone an existing container 101 to a new container 300 with a 4GB root
 207 file system, using pipes
 208
 209  # vzdump 101 --stdout | pct restore --rootfs 4 300 -
 210
 211
 212 ifdef::manvolnum[]
 213 include::pve-copyright.adoc[]
 214 endif::manvolnum[]
 215