add [--readd] [-s secondary_ip] {nodename}
Adds the given node to the cluster.
This command is used to join a new node to the cluster. You will have to provide the password for root of the node to be able to add the node in the cluster. The command needs to be run on the ganeti master.
Note that the command is potentially destructive, as it will forcibly join the specified host the cluster, not paying attention to its current status (it could be already in a cluster, etc.)
The -s is used in dual-home clusters and
specifies the new node's IP in the secondary network. See the
discussion in gnt-cluster(8) for more
information.
In case you're readding a node after hardware failure, you can
use the --readd parameter. In this case, you
don't need to pass the secondary IP again, it will reused from
the cluster. Also, the drained and
offline flags of the node will be cleared
before re-adding it.
Example:
# gnt-node add node5.example.com
# gnt-node add -s 192.168.44.5 node5.example.com
add-tags [--from file] {nodename} {tag...}
Add tags to the given node. 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.
evacuate [-f] [--iallocator NAME | --new-secondary destination_node] {node}
This command will move all secondary instances away from the given node. It works only for instances having a drbd disk template.
The new location for the instances can be specified in two ways:
as a single node for all instances, via the
--new-secondary option
or via the --iallocator option,
giving a script name as parameter, so each instance will
be in turn placed on the (per the script) optimal
node
Example:
# gnt-node evacuate -I dumb node3.example.com
failover [-f] [--ignore-consistency] {node}
This command will fail over all instances having the given node as primary to their secondary nodes. This works only for instances having a drbd disk template.
Normally the failover will check the consistency of the disks
before failing over the instance. If you are trying to migrate
instances off a dead node, this will fail. Use the
--ignore-consistency option for this purpose.
Example:
# gnt-node failover node1.example.com
info [node...]
Show detailed information about the nodes in the cluster. If you don't give any arguments, all nodes will be shows, otherwise the output will be restricted to the given names.
list [--sync]
[--no-headers] [--separator=SEPARATOR]
[--units=UNITS] [-o [+]FIELD,...]
[node...]
Lists the nodes 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 units used to display the numeric values in the output
varies, depending on the options given. By default, the values
will be formatted in the most appropriate unit. If the
--separator option is given, then the values
are shown in mebibytes to allow parsing by scripts. In both
cases, the --units option can be used to
enforce a given output unit.
By default, the query of nodes will be done in parallel with
any running jobs. This might give inconsistent results for the
free disk/memory. The --sync can be used to
grab locks for all the nodes and ensure consistent view of the
cluster (but this might stall the query for a long time).
The -o option takes a comma-separated list of
output fields. The available fields and their meaning are:
the node name
the number of instances having this node as primary
the list of instances having this node as primary, comma separated
the number of instances having this node as a secondary node
the list of instances having this node as a secondary node, comma separated
the primary ip of this node (used for cluster communication)
the secondary ip of this node (used for data replication in dual-ip clusters, see gnt-cluster(8)
total disk space in the volume group used for instance disk allocations
available disk space in the volume group
total memory on the physical node
the memory used by the node itself
memory available for instance allocations
the node bootid value; this is a linux specific feature that assigns a new UUID to the node at each boot and can be use to detect node reboots (by tracking changes in this value)
comma-separated list of the node's tags
the so called 'serial number' of the instance; this is a numeric field that is incremented each time the instance is modified, and it can be used to detect modifications
the toal number of logical processors
the number of NUMA domains on the node, if the hypervisor can export this information
the number of physical CPU sockets, if the hypervisor can export this information
whether the node is a master candidate or not
whether the node is drained or not; the cluster still communicates with drained nodes but excludes them from allocation operations
whether the node is offline or not; if offline, the cluster does not communicate with offline nodes; useful for nodes that are not reachable in order to avoid delays
A condensed version of the node flags; this field will output a one-character field, with the following possible values:
M for the master node
C for a master candidate
R for a regular node
D for a drained node
O for an offline node
If the value of the option starts with the character
+, the new fields will be added to the
default list. This allows to quickly see the default list plus
a few other fields, instead of retyping the entire list of
fields.
Note that some of this fields are known from the configuration of the cluster (e.g. name, pinst, sinst, pip, sip and thus the master does not need to contact the node for this data (making the listing fast if only fields from this set are selected), whereas the other fields are "live" fields and we need to make a query to the cluster nodes.
Depending on the virtualization type and implementation details, the mtotal, mnode and mfree may have slighly varying meanings. For example, some solutions share the node memory with the pool of memory used for instances (KVM), whereas others have separate memory for the node and for the instances (Xen).
If no node names are given, then all nodes are queried. Otherwise, only the given nodes will be listed.
migrate [-f] [--non-live] {node}
This command will migrate all instances having the given node as primary to their secondary nodes. This works only for instances having a drbd disk template.
As for the gnt-instance migrate command,
the --no-live option can be given to do a
non-live migration.
Example:
# gnt-node migrate node1.example.com
modify [-f] [--submit] [--master-candidate=yes|no] [--drained=yes|no] [--offline=yes|no] {node}
This command changes the role of the node. Each options takes either a literal yes or no, and only one option should be given as yes. The meaning of the roles are described in the manpage ganeti(7).
In case a node is demoted from the master candidate role, but
there are not enough new nodes for this case, the operation
will be refused. To override this check, pass the
--force option.
Example (setting a node offline, which will demote it from master candidate role if is in that role):
# gnt-node modify --offline=yes node1.example.com
Example (setting the node back to online and master candidate):
# gnt-node modify --offline=no --master-candidate=yes node1.example.com
remove {nodename}
Removes a node from the cluster. Instances must be removed or migrated to another cluster before.
Example:
# gnt-node remove node5.example.com
remove-tags [--from file] {nodename} {tag...}
Remove tags from the given node. 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 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.
volumes [--no-headers] [--human-readable] [--separator=SEPARATOR] [--output=FIELDS]
[node...]
Lists all logical volumes and their physical disks from the node(s) provided.
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 units used to display the numeric values in the output
varies, depending on the options given. By default, the values
will be formatted in the most appropriate unit. If the
--separator option is given, then the values
are shown in mebibytes to allow parsing by scripts. In both
cases, the --units option can be used to
enforce a given output unit.
The -o option takes a comma-separated list of
output fields. The available fields and their meaning are:
the node name on which the volume exists
the physical drive (on which the LVM physical volume lives)
the volume group name
the logical volume name
the logical volume size
The name of the instance to which this volume belongs, or (in case it's an orphan volume) the character "-"
Example:
# gnt-node volumes node5.example.com
Node PhysDev VG Name Size Instance
node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11000.meta 128 instance1.example.com
node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11001.data 256 instance1.example.com
Report bugs to http://code.google.com/p/ganeti/ or contact the developers using the ganeti mailing list <ganeti@googlegroups.com>.
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-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).
Copyright (C) 2006, 2007, 2008, 2009 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.