gnt-group(8) Version 2.5.2 gnt-group(8)
Name
gnt-group - Ganeti node-group administration
Synopsis
gnt-group {command} [arguments...]
DESCRIPTION
The gnt-group command is used for node group administration in the Ganeti system.
COMMANDS
ADD
add
[--node-parameters=NDPARAMS]
[--alloc-policy=POLICY]
{group}
Creates a new group with the given name. The node group will be initially empty; to add nodes to it, use gnt-group assign-nodes.
The --node-parameters option allows you to set default node parameters for nodes in the group. Please see ganeti(7) for more information
about supported key=value pairs.
The --alloc-policy option allows you to set an allocation policy for the group at creation time. Possible values are:
unallocable
nodes in the group should not be candidates for instance allocation, and the operation (e.g., instance creation) should fail if only
groups in this state could be found to satisfy the requirements.
last_resort
nodes in the group should not be used for instance allocations, unless this would be the only way to have the operation succeed.
preferred
nodes in the group can be used freely for allocation of instances (this is the default). Note that prioritization among groups in
this state will be deferred to the iallocator plugin that's being used.
ASSIGN-NODES
assign-nodes
[--force]
{group} {node...}
Assigns one or more nodes to the specified group, moving them from their original group (or groups).
By default, this command will refuse to proceed if the move would split between groups any instance that was not previously split (a split
instance is an instance with a mirrored disk template, e.g. DRBD, that has the primary and secondary nodes in different node groups). You
can force the operation with --force.
MODIFY
modify
[--node-parameters=NDPARAMS]
[--alloc-policy=POLICY]
{group}
Modifies some parameters from the node group.
The --node-parameters and --alloc-policy optiosn are documented in the add command above.
REMOVE
remove {group}
Deletes the indicated node group, which must be empty. There must always be at least one group, so the last group cannot be removed.
LIST
list [--no-headers] [--separator=SEPARATOR] [-v]
[-o [+]FIELD,...] [--filter] [group...]
Lists all existing node groups in the cluster.
The --no-headers option will skip the initial header line. The --separator option takes an argument which denotes what will be used
between the output fields. Both these options are to help scripting.
The -v option activates verbose mode, which changes the display of special field states (see ganeti(7)).
The -o option takes a comma-separated list of output fields. If the value of the option starts with the character +, the new fields will be
added to the default list. This allows one to quickly see the default list plus a few other fields, instead of retyping the entire list of
fields.
The available fields and their meaning are:
alloc_policy
Allocation policy for group
ctime Creation timestamp
mtime Modification timestamp
name Group name
ndparams
Node parameters
node_cnt
Number of nodes
node_list
List of nodes
pinst_cnt
Number of primary instances
pinst_list
List of primary instances
serial_no
Group object serial number, incremented on each modification
tags Tags
uuid Group UUID
If exactly one argument is given and it appears to be a query filter (see ganeti(7)), the query result is filtered accordingly. For ambigu-
ous cases (e.g. a single field name as a filter) the --filter (-F) option forces the argument to be treated as a filter.
If no group names are given, then all groups are included. Otherwise, only the named groups will be listed.
LIST-FIELDS
list-fields [field...]
List available fields for node groups.
RENAME
rename {oldname} {newname}
Renames a given group from oldname to newname.
EVACUATE
evacuate [--iallocator NAME] [--to GROUP...] {group}
This command will move all instances out of the given node group. Instances are placed in a new group by an iallocator, either given on
the command line or as a cluster default.
If no specific destination groups are specified using --to, all groups except the evacuated group are considered.
Example:
# gnt-group evacuate -I hail --to rack4 rack1
TAGS
ADD-TAGS
add-tags [--from file] {groupname} {tag...}
Add tags to the given node group. If any of the tags contains invalid characters, the entire operation will abort.
If the --from option is given, the list of tags will be extended with the contents of that file (each line becomes a tag). In this case,
there is not need to pass tags on the command line (if you do, both sources will be used). A file name of - will be interpreted as stdin.
LIST-TAGS
list-tags {groupname}
List the tags of the given node group.
REMOVE-TAGS
remove-tags [--from file] {groupname} {tag...}
Remove tags from the given node group. If any of the tags are not existing on the node, the entire operation will abort.
If the --from option is given, the list of tags to be removed will be extended with the contents of that file (each line becomes a tag). In
this case, there is not need to pass tags on the command line (if you do, tags from both sources will be removed). A file name of - will be
interpreted as stdin.
REPORTING BUGS
Report bugs to project website (http://code.google.com/p/ganeti/) or contact the developers using the Ganeti mailing list (ganeti@google-
groups.com).
SEE ALSO
Ganeti overview and specifications: ganeti(7) (general overview), ganeti-os-interface(7) (guest OS definitions).
Ganeti commands: gnt-cluster(8) (cluster-wide commands), gnt-job(8) (job-related commands), gnt-node(8) (node-related commands), gnt-
instance(8) (instance commands), gnt-os(8) (guest OS commands), gnt-group(8) (node group commands), gnt-backup(8) (instance import/export
commands), gnt-debug(8) (debug commands).
Ganeti daemons: ganeti-watcher(8) (automatic instance restarter), ganeti-cleaner(8) (job queue cleaner), ganeti-noded(8) (node daemon),
ganeti-masterd(8) (master daemon), ganeti-rapi(8) (remote API daemon).
Ganeti htools: htools(1) (generic binary), hbal(1) (cluster balancer), hspace(1) (capacity calculation), hail(1) (IAllocator plugin),
hscan(1) (data gatherer from remote clusters).
COPYRIGHT
Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Google Inc. Permission is granted to copy, distribute and/or modify under the terms of
the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
version.
On Debian systems, the complete text of the GNU General Public License can be found in /usr/share/common-licenses/GPL.
Ganeti gnt-group(8)