gnt-group

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 [–submit]

[–node-parameters=*NDPARAMS*]

[–alloc-policy=*POLICY*]

[{-D|–disk-parameters} disk-template:disk-param*=*value*[,*disk-param*=*value...]]

[–ipolicy-bounds-specs bound_ispecs]

[–ipolicy-disk-templates template [,*template*...]]

[–ipolicy-spindle-ratio ratio]

[–ipolicy-vcpu-ratio ratio]

[–disk-state diskstate]

[–hypervisor-state hvstate]

{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 and their corresponding options.

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.

The -D (--disk-parameters) option allows you to set the disk parameters for the node group; please see the section about gnt-cluster add in gnt-cluster(8) for more information about disk parameters

The --ipolicy-... options specify instance policies on the node group, and are documented in the gnt-cluster(8) man page.

See ganeti(7) for a description of --submit and other common options.

ASSIGN-NODES

assign-nodes

[–force] [–submit]

{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.

See ganeti(7) for a description of --submit and other common options.

MODIFY

modify [–submit]

[–node-parameters=*NDPARAMS*]

[–alloc-policy=*POLICY*]

[–hypervisor-state hvstate]

[{-D|–disk-parameters} disk-template:disk-param*=*value*[,*disk-param*=*value...]]

[–disk-state diskstate]

[–ipolicy-bounds-specs bound_ispecs]

[–ipolicy-disk-templates template [,*template*...]]

[–ipolicy-spindle-ratio ratio]

[–ipolicy-vcpu-ratio ratio]

{group}

Modifies some parameters from the node group.

The --node-parameters and --alloc-policy options are documented in the add command above. --hypervisor-state as well as --disk-state are documented in detail in ganeti(7).

The --node-parameters, --alloc-policy, -D (--disk-parameters) options are documented in the add command above.

The --ipolicy-... options specify instance policies on the node group, and are documented in the gnt-cluster(8) man page.

See ganeti(7) for a description of --submit and other common options.

REMOVE

remove [–submit] {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.

See ganeti(7) for a description of --submit and other common options.

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

custom_diskparams

Custom disk parameters

custom_ipolicy

Custom instance policy limitations

custom_ndparams

Custom node parameters

diskparams

Disk parameters (merged)

ipolicy

Instance policy limitations (merged)

mtime

Modification timestamp

name

Group name

ndp/exclusive_storage

The “exclusive_storage” node parameter

ndp/oob_program

The “oob_program” node parameter

ndp/spindle_count

The “spindle_count” node parameter

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 ambiguous 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 [–submit] {oldname} {newname}

Renames a given group from oldname to newname.

See ganeti(7) for a description of --submit and other common options.

EVACUATE

evacuate [–submit] [–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.

See ganeti(7) for a description of --submit and other common options.

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.

INFO

info [group...]

Shows config information for all (or given) groups.

SHOW-ISPECS-CMD

show-ispecs-cmd [–include-defaults] [group...]

Shows the command line that can be used to recreate the given groups (or all groups, if none is given) with the same options relative to specs in the instance policies.

If --include-defaults is specified, include also the default values (i.e. the cluster-level settings), and not only the configuration items that a group overrides.