+[[chapter_vzdump]]
ifdef::manvolnum[]
-PVE({manvolnum})
-================
+vzdump(1)
+=========
include::attributes.txt[]
+:pve-toplevel:
NAME
----
vzdump - Backup Utility for VMs and Containers
-SYNOPSYS
+SYNOPSIS
--------
include::vzdump.1-synopsis.adoc[]
DESCRIPTION
-----------
endif::manvolnum[]
-
ifndef::manvolnum[]
Backup and Restore
==================
include::attributes.txt[]
endif::manvolnum[]
+ifdef::wiki[]
+:pve-toplevel:
+endif::wiki[]
+
+Backups are a requirements for any sensible IT deployment, and {pve}
+provides a fully integrated solution, using the capabilities of each
+storage and each guest system type. This allows the system
+administrator to fine tune via the `mode` option between consistency
+of the backups and downtime of the guest system.
+
+{pve} backups are always full backups - containing the VM/CT
+configuration and all data. Backups can be started via the GUI or via
+the `vzdump` command line tool.
+
+.Backup Storage
+
+Before a backup can run, a backup storage must be defined. Refer to
+the Storage documentation on how to add a storage. A backup storage
+must be a file level storage, as backups are stored as regular files.
+In most situations, using a NFS server is a good way to store backups.
+You can save those backups later to a tape drive, for off-site
+archiving.
+
+.Scheduled Backup
+
+Backup jobs can be scheduled so that they are executed automatically
+on specific days and times, for selectable nodes and guest systems.
+Configuration of scheduled backups is done at the Datacenter level in
+the GUI, which will generate a cron entry in /etc/cron.d/vzdump.
+
+Backup modes
+------------
-'vzdump' is a utility to make consistent snapshots of running guest
-systems. It basically creates an archive of the guest private
-area, which also includes the guest configuration files. 'vzdump'
-currently supports LXC containers and QemuServer VMs.
+There are several ways to provide consistency (option `mode`),
+depending on the guest type.
-There are several ways to provide consistency (option `mode`):
+.Backup modes for VMs:
`stop` mode::
-Stop the guest during backup. This results in a very long downtime.
+This mode provides the highest consistency of the backup, at the cost
+of a downtime in the VM operation. It works by executing an orderly
+shutdown of the VM, and then runs a background Qemu process to backup
+the VM data. After the backup is complete, the Qemu process resumes
+the VM to full operation mode if it was previously running.
`suspend` mode::
-For containers, this mode uses rsync to copy the container data to a temporary
-location (see option `--tmpdir`). Then the container is suspended and a second
-rsync copies changed files. After that, the container is started (resumed)
-again. This results in minimal downtime, but needs additional space
-to hold the container copy.
-+
-When the container is on a local filesystem and the target storage of the backup
-is an NFS server, you should set `--tmpdir` to reside on a local filesystem too,
-as this will result in a many fold performance improvement.
-Use of a local `tmpdir` is also required if you want to backup in `suspend`
-mode a local container using ACLs to an NFS server.
-+
-For QemuServer, this mode will suspend the VM, start
-a live backup, and resume the VM. This does not require a temporary
-storage.
+This mode is provided for compatibility reason, and suspends the VM
+before calling the `snapshot` mode. Since suspending the VM results in
+a longer downtime and does not necessarily improve the data
+consistency, the use of the `snapshot` mode is recommended instead.
`snapshot` mode::
-For containers, this mode uses the snapshotting facilities of the
-underlying storage. A snapshot will be made of the container volume,
-and the snapshot content will be archived in a tar file.
-+
-For QemuServer, this mode will do a live backup similar to the
-`suspend` mode, but without suspending/resuming the VM.
+This mode provides the lowest operation downtime, at the cost of a
+small inconstancy risk. It works by performing a Proxmox VE live
+backup, in which data blocks are copied while the VM is running. If the
+guest agent is enabled (`agent: 1`) and running, it calls
+`guest-fsfreeze-freeze` and `guest-fsfreeze-thaw` to improve
+consistency.
A technical overview of the Proxmox VE live backup for QemuServer can
be found online
-https://git.proxmox.com/?p=pve-qemu-kvm.git;a=blob;f=backup.txt[here],
+https://git.proxmox.com/?p=pve-qemu-kvm.git;a=blob;f=backup.txt[here].
+
+NOTE: Proxmox VE live backup provides snapshot-like semantics on any
+storage type. It does not require that the underlying storage supports
+snapshots.
+
+.Backup modes for Containers:
+
+`stop` mode::
+
+Stop the container for the duration of the backup. This potentially
+results in a very long downtime.
+
+`suspend` mode::
+
+This mode uses rsync to copy the container data to a temporary
+location (see option `--tmpdir`). Then the container is suspended and
+a second rsync copies changed files. After that, the container is
+started (resumed) again. This results in minimal downtime, but needs
+additional space to hold the container copy.
++
+When the container is on a local file system and the target storage of
+the backup is an NFS server, you should set `--tmpdir` to reside on a
+local file system too, as this will result in a many fold performance
+improvement. Use of a local `tmpdir` is also required if you want to
+backup a local container using ACLs in suspend mode if the backup
+storage is an NFS server.
+
+`snapshot` mode::
+
+This mode uses the snapshotting facilities of the underlying
+storage. First, the container will be suspended to ensure data consistency.
+A temporary snapshot of the container's volumes will be made and the
+snapshot content will be archived in a tar file. Finally, the temporary
+snapshot is deleted again.
+
+NOTE: `snapshot` mode requires that all backed up volumes are on a storage that
+supports snapshots. Using the `backup=no` mount point option individual volumes
+can be excluded from the backup (and thus this requirement).
+
+NOTE: bind and device mount points are skipped during backup operations, like
+volume mount points with the backup option disabled.
+
Backup File Names
-----------------
-Newer versions of vzdump encode the virtual machine type and the
+Newer versions of vzdump encode the guest type and the
backup time into the filename, for example
vzdump-lxc-105-2009_10_09-11_04_43.tar
Configuration
-------------
-Global configuration is stored in '/etc/vzdump.conf'.
-
- tmpdir: DIR
- dumpdir: DIR
- storage: STORAGE_ID
- mode: snapshot|suspend|stop
- bwlimit: KBPS
- ionize: PRI
- lockwait: MINUTES
- stopwait: MINUTES
- size: MB
- maxfiles: N
- script: FILENAME
- exclude-path: PATHLIST
+Global configuration is stored in `/etc/vzdump.conf`. The file uses a
+simple colon separated key/value format. Each line has the following
+format:
+
+ OPTION: value
+
+Blank lines in the file are ignored, and lines starting with a `#`
+character are treated as comments and are also ignored. Values from
+this file are used as default, and can be overwritten on the command
+line.
+
+We currently support the following options:
+
+include::vzdump.conf.5-opts.adoc[]
+
+
+.Example `vzdump.conf` Configuration
+----
+tmpdir: /mnt/fast_local_disk
+storage: my_backup_storage
+mode: snapshot
+bwlimit: 10000
+----
Hook Scripts
------------
You can specify a hook script with option `--script`. This script is
called at various phases of the backup process, with parameters
accordingly set. You can find an example in the documentation
-directory ('vzdump-hook-script.pl').
+directory (`vzdump-hook-script.pl`).
File Exclusions
---------------
-First, this option is only available for container backups. 'vzdump'
-skips the following files with option `--stdexcludes`
+NOTE: this option is only available for container backups.
+
+`vzdump` skips the following files by default (disable with the option
+`--stdexcludes 0`)
- /var/log/?*
/tmp/?*
/var/tmp/?*
/var/run/?*pid
-Or you can manually specify exclude paths, for example:
+You can also manually specify (additional) exclude paths, for example:
# vzdump 777 --exclude-path /tmp/ --exclude-path '/var/foo*'
(only excludes tmp directories)
Configuration files are also stored inside the backup archive
-(`/etc/vzdump/`), and will be correctly restored.
+(in `./etc/vzdump/`) and will be correctly restored.
Examples
--------
Simply dump guest 777 - no snapshot, just archive the guest private area and
configuration files to the default dump directory (usually
-'/var/liv//vz/dump/').
+`/var/lib/vz/dump/`).
# vzdump 777
# vzdump --all --mode suspend --mailto root --mailto admin
-Use snapshot mode (no downtime).
+Use snapshot mode (no downtime) and non-default dump directory.
# vzdump 777 --dumpdir /mnt/backup --mode snapshot
projects / pve-docs.git / blobdiff