From 28f3c2dde7c2bea2e82d40fb55ce030394e0d203 Mon Sep 17 00:00:00 2001 From: Iustin Pop <iustin@google.com> Date: Sat, 13 Nov 2010 19:50:32 +0100 Subject: [PATCH] Add RST version of gnt-backup man page MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Iustin Pop <iustin@google.com> Reviewed-by: RenΓ© Nussbaumer <rn@google.com> --- man/gnt-backup.rst | 226 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 226 insertions(+) create mode 100644 man/gnt-backup.rst diff --git a/man/gnt-backup.rst b/man/gnt-backup.rst new file mode 100644 index 000000000..a8bd39810 --- /dev/null +++ b/man/gnt-backup.rst @@ -0,0 +1,226 @@ +gnt-backup(8) Ganeti | Version @GANETI_VERSION@ +=============================================== + +Name +---- + +gnt-backup - Ganeti instance import/export + +Synopsis +-------- + +**gnt-backup** {command} [arguments...] + +DESCRIPTION +----------- + +The **gnt-backup** is used for importing and exporting instances +and their configuration from a Ganeti system. It is useful for +backing up instances and also to migrate them between clusters. + +COMMANDS +-------- + +EXPORT +~~~~~~ + +**export** {-n *node*} [--shutdown-timeout=*N*] [--noshutdown] +[--remove-instance] [--ignore-remove-failures] {*instance*} + +Exports an instance to the target node. All the instance data and +its configuration will be exported under the +/srv/ganeti/export/*instance* directory on the target node. + +The ``--shutdown-timeout`` is used to specify how much time to wait +before forcing the shutdown (xm destroy in xen, killing the kvm +process, for kvm). By default two minutes are given to each +instance to stop. + +The ``--noshutdown`` option will create a snapshot disk of the +instance without shutting it down first. While this is faster and +involves no downtime, it cannot be guaranteed that the instance +data will be in a consistent state in the exported dump. + +The ``--remove`` option can be used to remove the instance after it +was exported. This is useful to make one last backup before +removing the instance. + +The exit code of the command is 0 if all disks were backed up +successfully, 1 if no data was backed up or if the configuration +export failed, and 2 if just some of the disks failed to backup. +The exact details of the failures will be shown during the command +execution (and will be stored in the job log). It is recommended +that for any non-zero exit code, the backup is considered invalid, +and retried. + +Example:: + + # gnt-backup export -n node1.example.com instance3.example.com + + +IMPORT +~~~~~~ + +| **import** +| {-n *node[:secondary-node]* | --iallocator *name*} +| [--disk *N*:size=*VAL* [,mode=*ro|rw*]...] +| [--net *N* [:options...] | --no-nics] +| [-B *BEPARAMS*] +| [-H *HYPERVISOR* [: option=*value*... ]] +| [--src-node=*source-node*] [--src-dir=*source-dir*] +| [-t [diskless | plain | drbd | file]] +| [--identify-defaults] +| {*instance*} + +Imports a new instance from an export residing on *source-node* in +*source-dir*. *instance* must be in DNS and resolve to a IP in the +same network as the nodes in the cluster. If the source node and +directory are not passed, the last backup in the cluster is used, +as visible with the **list** command. + +The ``disk`` option specifies the parameters for the disks of the +instance. The numbering of disks starts at zero. For each disk, at +least the size needs to be given, and optionally the access mode +(read-only or the default of read-write) can also be specified. The +size is interpreted (when no unit is given) in mebibytes. You can +also use one of the suffixes m, g or t to specificy the exact the +units used; these suffixes map to mebibytes, gibibytes and +tebibytes. + +Alternatively, a single-disk instance can be created via the ``-s`` +option which takes a single argument, the size of the disk. This is +similar to the Ganeti 1.2 version (but will only create one disk). + +If no disk information is passed, the disk configuration saved at +export time will be used. + +The minimum disk specification is therefore empty (export information +will be used), a single disk can be specified as ``--disk 0:size=20G`` +(or ``-s 20G`` when using the ``-s`` option), and a three-disk +instance can be specified as ``--disk 0:size=20G --disk 1:size=4G +--disk 2:size=100G``. + +The NICs of the instances can be specified via the ``--net`` +option. By default, the NIC configuration of the original +(exported) instance will be reused. Each NIC can take up to three +parameters (all optional): + +mac + either a value or ``generate`` to generate a new unique MAC, or + ``auto`` to reuse the old MAC + +ip + specifies the IP address assigned to the instance from the Ganeti + side (this is not necessarily what the instance will use, but what + the node expects the instance to use) + +mode + specifies the connection mode for this nic: ``routed`` or + ``bridged``. + +link + in bridged mode specifies the bridge to attach this NIC to, in + routed mode it's intended to differentiate between different + routing tables/instance groups (but the meaning is dependent on + the network script in use, see **gnt-cluster**(8) for more + details) + +Of these ``mode`` and ``link`` are nic parameters, and inherit their +default at cluster level. + +If no network is desired for the instance, you should create a single +empty NIC and delete it afterwards via **gnt-instance modify --net +delete**. + +The ``-B`` option specifies the backend parameters for the +instance. If no such parameters are specified, the values are +inherited from the export. Possible parameters are: + +memory + the memory size of the instance; as usual, suffixes can be used to + denote the unit, otherwise the value is taken in mebibites + +vcpus + the number of VCPUs to assign to the instance (if this value makes + sense for the hypervisor) + +auto_balance + whether the instance is considered in the N+1 cluster checks + (enough redundancy in the cluster to survive a node failure) + + +The ``-t`` options specifies the disk layout type for the instance. +If not passed, the configuration of the original instance is used. +The available choices are: + +diskless + This creates an instance with no disks. Its useful for testing only + (or other special cases). + +plain + Disk devices will be logical volumes. + +drbd + Disk devices will be drbd (version 8.x) on top of lvm volumes. + +file + Disk devices will be backed up by files, under the directory + ``@RPL_FILE_STORAGE_DIR@``. By default, each instance will get a + directory (as its own name) under this path, and each disk is + stored as individual files in this (instance-specific) directory. + + +The ``--iallocator`` option specifies the instance allocator plugin +to use. If you pass in this option the allocator will select nodes +for this instance automatically, so you don't need to pass them +with the ``-n`` option. For more information please refer to the +instance allocator documentation. + +The optional second value of the ``--node`` is used for the drbd +template and specifies the remote node. + +Since many of the parameters are by default read from the exported +instance information and used as such, the new instance will have +all parameters explicitly specified, the opposite of a newly added +instance which has most parameters specified via cluster defaults. +To change the import behaviour to recognize parameters whose saved +value matches the current cluster default and mark it as such +(default value), pass the ``--identify-defaults`` option. This will +affect the hypervisor, backend and NIC parameters, both read from +the export file and passed in via the command line. + +Example for identical instance import:: + + # gnt-backup import -n node1.example.com instance3.example.com + + +Explicit configuration example:: + + # gnt-backup import -t plain --disk 0:size=1G -B memory=512 \ + > -n node1.example.com \ + > instance3.example.com + + +LIST +~~~~ + +**list** [--node=*NODE*] + +Lists the exports currently available in the default directory in +all the nodes of the current cluster, or optionally only a subset +of them specified using the ``--node`` option (which can be used +multiple times) + +Example:: + + # gnt-backup list --nodes node1 --nodes node2 + + +REMOVE +~~~~~~ + +**remove** {instance_name} + +Removes the backup for the given instance name, if any. If the backup +was for a deleted instance, it is needed to pass the FQDN of the +instance, and not only the short hostname. -- GitLab