1 gnt-node(8) Ganeti | Version @GANETI_VERSION@
2 =============================================
7 gnt-node - Node administration
12 **gnt-node** {command} [arguments...]
17 The **gnt-node** is used for managing the (physical) nodes in the
26 | **add** [--readd] [{-s|--secondary-ip} *secondary\_ip*]
27 | [{-g|--node-group} *nodegroup*]
28 | [--master-capable=``yes|no``] [--vm-capable=``yes|no``]
29 | [--node-parameters *ndparams*]
32 Adds the given node to the cluster.
34 This command is used to join a new node to the cluster. You will
35 have to provide the password for root of the node to be able to add
36 the node in the cluster. The command needs to be run on the Ganeti
39 Note that the command is potentially destructive, as it will
40 forcibly join the specified host the cluster, not paying attention
41 to its current status (it could be already in a cluster, etc.)
43 The ``-s (--secondary-ip)`` is used in dual-home clusters and
44 specifies the new node's IP in the secondary network. See the
45 discussion in **gnt-cluster**(8) for more information.
47 In case you're readding a node after hardware failure, you can use
48 the ``--readd`` parameter. In this case, you don't need to pass the
49 secondary IP again, it will reused from the cluster. Also, the
50 drained and offline flags of the node will be cleared before
53 The ``--force-join`` option is to proceed with adding a node even if it already
54 appears to belong to another cluster. This is used during cluster merging, for
57 The ``-g (--node-group)`` option is used to add the new node into a
58 specific node group, specified by UUID or name. If only one node group
59 exists you can skip this option, otherwise it's mandatory.
61 The ``vm_capable``, ``master_capable`` and ``ndparams`` options are
62 described in **ganeti**(7), and are used to set the properties of the
67 # gnt-node add node5.example.com
68 # gnt-node add -s 192.0.2.5 node5.example.com
69 # gnt-node add -g group2 -s 192.0.2.9 node9.group2.example.com
75 **add-tags** [--from *file*] {*nodename*} {*tag*...}
77 Add tags to the given node. If any of the tags contains invalid
78 characters, the entire operation will abort.
80 If the ``--from`` option is given, the list of tags will be
81 extended with the contents of that file (each line becomes a tag).
82 In this case, there is not need to pass tags on the command line
83 (if you do, both sources will be used). A file name of - will be
89 **evacuate** [-f] [--early-release] [--iallocator *NAME* \|
90 --new-secondary *destination\_node*]
91 [--primary-only \| --secondary-only] [--early-release] {*node*}
93 This command will move instances away from the given node. If
94 ``--primary-only`` is given, only primary instances are evacuated, with
95 ``--secondary-only`` only secondaries. If neither is given, all
96 instances are evacuated. It works only for instances having a drbd disk
99 The new location for the instances can be specified in two ways:
101 - as a single node for all instances, via the ``-n (--new-secondary)``
104 - or via the ``-I (--iallocator)`` option, giving a script name as
105 parameter, so each instance will be in turn placed on the (per the
108 The ``--early-release`` changes the code so that the old storage on
109 node being evacuated is removed early (before the resync is
110 completed) and the internal Ganeti locks are also released for both
111 the current secondary and the new secondary, thus allowing more
112 parallelism in the cluster operation. This should be used only when
113 recovering from a disk failure on the current secondary (thus the
114 old storage is already broken) or when the storage on the primary
115 node is known to be fine (thus we won't need the old storage for
118 Note that this command is equivalent to using per-instance commands for
119 each affected instance individually:
121 - ``--primary-only`` is equivalent to ``gnt-instance failover/migration``
122 - ``--secondary-only`` is equivalent to ``gnt-instance replace-disks``
123 in the secondary node change mode (only valid for DRBD instances)
124 - when neither of the above is done a combination of the two cases is run
128 # gnt-node evacuate -I hail node3.example.com
134 **failover** [-f] [--ignore-consistency] {*node*}
136 This command will fail over all instances having the given node as
137 primary to their secondary nodes. This works only for instances having
138 a drbd disk template.
140 Normally the failover will check the consistency of the disks before
141 failing over the instance. If you are trying to migrate instances off
142 a dead node, this will fail. Use the ``--ignore-consistency`` option
147 # gnt-node failover node1.example.com
155 Show detailed information about the nodes in the cluster. If you
156 don't give any arguments, all nodes will be shows, otherwise the
157 output will be restricted to the given names.
163 | [--no-headers] [--separator=*SEPARATOR*]
164 | [--units=*UNITS*] [-v] [{-o|--output} *[+]FIELD,...*]
168 Lists the nodes in the cluster.
170 The ``--no-headers`` option will skip the initial header line. The
171 ``--separator`` option takes an argument which denotes what will be
172 used between the output fields. Both these options are to help
175 The units used to display the numeric values in the output varies,
176 depending on the options given. By default, the values will be
177 formatted in the most appropriate unit. If the ``--separator``
178 option is given, then the values are shown in mebibytes to allow
179 parsing by scripts. In both cases, the ``--units`` option can be
180 used to enforce a given output unit.
182 Queries of nodes will be done in parallel with any running jobs. This might
183 give inconsistent results for the free disk/memory.
185 The ``-v`` option activates verbose mode, which changes the display of
186 special field states (see **ganeti(7)**).
188 The ``-o (--output)`` option takes a comma-separated list of output
189 fields. The available fields and their meaning are:
193 If the value of the option starts with the character ``+``, the new
194 fields will be added to the default list. This allows one to quickly
195 see the default list plus a few other fields, instead of retyping
196 the entire list of fields.
198 Note that some of these fields are known from the configuration of the
199 cluster (e.g. ``name``, ``pinst``, ``sinst``, ``pip``, ``sip``) and thus
200 the master does not need to contact the node for this data (making the
201 listing fast if only fields from this set are selected), whereas the
202 other fields are "live" fields and require a query to the cluster nodes.
204 Depending on the virtualization type and implementation details, the
205 ``mtotal``, ``mnode`` and ``mfree`` fields may have slighly varying
206 meanings. For example, some solutions share the node memory with the
207 pool of memory used for instances (KVM), whereas others have separate
208 memory for the node and for the instances (Xen).
210 If exactly one argument is given and it appears to be a query filter
211 (see **ganeti(7)**), the query result is filtered accordingly. For
212 ambiguous cases (e.g. a single field name as a filter) the ``--filter``
213 (``-F``) option forces the argument to be treated as a filter (e.g.
214 ``gnt-node list -F master_candidate``).
216 If no node names are given, then all nodes are queried. Otherwise,
217 only the given nodes will be listed.
223 **list-fields** [field...]
225 Lists available fields for nodes.
231 **list-tags** {*nodename*}
233 List the tags of the given node.
238 **migrate** [-f] [--non-live] [--migration-mode=live\|non-live]
241 This command will migrate all instances having the given node as
242 primary to their secondary nodes. This works only for instances
243 having a drbd disk template.
245 As for the **gnt-instance migrate** command, the options
246 ``--no-live`` and ``--migration-mode`` can be given to influence
251 # gnt-node migrate node1.example.com
257 | **modify** [-f] [--submit]
258 | [{-C|--master-candidate} ``yes|no``]
259 | [{-D|--drained} ``yes|no``] [{-O|--offline} ``yes|no``]
260 | [--master-capable=``yes|no``] [--vm-capable=``yes|no``] [--auto-promote]
261 | [{-s|--secondary-ip} *secondary_ip*]
262 | [--node-parameters *ndparams*]
263 | [--node-powered=``yes|no``]
266 This command changes the role of the node. Each options takes
267 either a literal yes or no, and only one option should be given as
268 yes. The meaning of the roles and flags are described in the
269 manpage **ganeti**(7).
271 The option ``--node-powered`` can be used to modify state-of-record if
272 it doesn't reflect the reality anymore.
274 In case a node is demoted from the master candidate role, the
275 operation will be refused unless you pass the ``--auto-promote``
276 option. This option will cause the operation to lock all cluster nodes
277 (thus it will not be able to run in parallel with most other jobs),
278 but it allows automated maintenance of the cluster candidate pool. If
279 locking all cluster node is too expensive, another option is to
280 promote manually another node to master candidate before demoting the
283 Example (setting a node offline, which will demote it from master
284 candidate role if is in that role)::
286 # gnt-node modify --offline=yes node1.example.com
288 The ``-s (--secondary-ip)`` option can be used to change the node's
289 secondary ip. No drbd instances can be running on the node, while this
290 operation is taking place.
292 Example (setting the node back to online and master candidate)::
294 # gnt-node modify --offline=no --master-candidate=yes node1.example.com
300 **remove** {*nodename*}
302 Removes a node from the cluster. Instances must be removed or
303 migrated to another cluster before.
307 # gnt-node remove node5.example.com
313 **remove-tags** [--from *file*] {*nodename*} {*tag*...}
315 Remove tags from the given node. If any of the tags are not
316 existing on the node, the entire operation will abort.
318 If the ``--from`` option is given, the list of tags to be removed will
319 be extended with the contents of that file (each line becomes a tag).
320 In this case, there is not need to pass tags on the command line (if
321 you do, tags from both sources will be removed). A file name of - will
322 be interpreted as stdin.
327 | **volumes** [--no-headers] [--human-readable]
328 | [--separator=*SEPARATOR*] [{-o|--output} *FIELDS*]
331 Lists all logical volumes and their physical disks from the node(s)
334 The ``--no-headers`` option will skip the initial header line. The
335 ``--separator`` option takes an argument which denotes what will be
336 used between the output fields. Both these options are to help
339 The units used to display the numeric values in the output varies,
340 depending on the options given. By default, the values will be
341 formatted in the most appropriate unit. If the ``--separator``
342 option is given, then the values are shown in mebibytes to allow
343 parsing by scripts. In both cases, the ``--units`` option can be
344 used to enforce a given output unit.
346 The ``-o (--output)`` option takes a comma-separated list of output
347 fields. The available fields and their meaning are:
350 the node name on which the volume exists
353 the physical drive (on which the LVM physical volume lives)
356 the volume group name
359 the logical volume name
362 the logical volume size
365 The name of the instance to which this volume belongs, or (in case
366 it's an orphan volume) the character "-"
371 # gnt-node volumes node5.example.com
372 Node PhysDev VG Name Size Instance
373 node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11000.meta 128 instance1.example.com
374 node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11001.data 256 instance1.example.com
380 | **list-storage** [--no-headers] [--human-readable]
381 | [--separator=*SEPARATOR*] [--storage-type=*STORAGE\_TYPE*]
382 | [{-o|--output} *FIELDS*]
385 Lists the available storage units and their details for the given
388 The ``--no-headers`` option will skip the initial header line. The
389 ``--separator`` option takes an argument which denotes what will be
390 used between the output fields. Both these options are to help
393 The units used to display the numeric values in the output varies,
394 depending on the options given. By default, the values will be
395 formatted in the most appropriate unit. If the ``--separator``
396 option is given, then the values are shown in mebibytes to allow
397 parsing by scripts. In both cases, the ``--units`` option can be
398 used to enforce a given output unit.
400 The ``--storage-type`` option can be used to choose a storage unit
401 type. Possible choices are lvm-pv, lvm-vg or file.
403 The ``-o (--output)`` option takes a comma-separated list of output
404 fields. The available fields and their meaning are:
407 the node name on which the volume exists
410 the type of the storage unit (currently just what is passed in via
414 the path/identifier of the storage unit
417 total size of the unit; for the file type see a note below
420 used space in the unit; for the file type see a note below
426 whether we the unit is available for allocation (only lvm-pv can
427 change this setting, the other types always report true)
430 Note that for the "file" type, the total disk space might not equal
431 to the sum of used and free, due to the method Ganeti uses to
432 compute each of them. The total and free values are computed as the
433 total and free space values for the filesystem to which the
434 directory belongs, but the used space is computed from the used
435 space under that directory *only*, which might not be necessarily
436 the root of the filesystem, and as such there could be files
437 outside the file storage directory using disk space and causing a
438 mismatch in the values.
442 node1# gnt-node list-storage node2
443 Node Type Name Size Used Free Allocatable
444 node2 lvm-pv /dev/sda7 673.8G 1.5G 672.3G Y
445 node2 lvm-pv /dev/sdb1 698.6G 0M 698.6G Y
451 **modify-storage** [``--allocatable=yes|no``]
452 {*node*} {*storage-type*} {*volume-name*}
454 Modifies storage volumes on a node. Only LVM physical volumes can
455 be modified at the moment. They have a storage type of "lvm-pv".
459 # gnt-node modify-storage --allocatable no node5.example.com lvm-pv /dev/sdb1
465 **repair-storage** [--ignore-consistency] {*node*} {*storage-type*}
468 Repairs a storage volume on a node. Only LVM volume groups can be
469 repaired at this time. They have the storage type "lvm-vg".
471 On LVM volume groups, **repair-storage** runs "vgreduce
476 **Caution:** Running this command can lead to data loss. Use it with
479 The ``--ignore-consistency`` option will ignore any inconsistent
480 disks (on the nodes paired with this one). Use of this option is
481 most likely to lead to data-loss.
485 # gnt-node repair-storage node5.example.com lvm-vg xenvg
491 **powercycle** [``--yes``] [``--force``] {*node*}
493 This command (tries to) forcefully reboot a node. It is a command
494 that can be used if the node environemnt is broken, such that the
495 admin can no longer login over ssh, but the Ganeti node daemon is
498 Note that this command is not guaranteed to work; it depends on the
499 hypervisor how effective is the reboot attempt. For Linux, this
500 command require that the kernel option CONFIG\_MAGIC\_SYSRQ is
503 The ``--yes`` option can be used to skip confirmation, while the
504 ``--force`` option is needed if the target node is the master
510 **power** [``--force``] [``--ignore-status``] [``--all``]
511 [``--power-delay``] on|off|cycle|status [*nodes*]
513 This command calls out to out-of-band management to change the power
514 state of given node. With ``status`` you get the power status as reported
515 by the out-of-band managment script.
517 Note that this command will only work if the out-of-band functionality
518 is configured and enabled on the cluster. If this is not the case,
519 please use the **powercycle** command above.
521 Using ``--force`` you skip the confirmation to do the operation.
522 Currently this only has effect on ``off`` and ``cycle``. On those two
523 you can *not* operate on the master. However, the command will provide
524 you with the command to invoke to operate on the master nerver-mind.
525 This is considered harmful and Ganeti does not support the use of it.
527 Providing ``--ignore-status`` will ignore the offline=N state of a node
528 and continue with power off.
530 ``--power-delay`` specifies the time in seconds (factions allowed)
531 waited between powering on the next node. This is by default 2 seconds
532 but can increased if needed with this option.
534 *nodes* are optional. If not provided it will call out for every node in
535 the cluster. Except for the ``off`` and ``cycle`` command where you've
536 to explicit use ``--all`` to select all.
544 This command calls out to out-of-band management to ask for the health status
545 of all or given nodes. The health contains the node name and then the items
546 element with their status in a ``item=status`` manner. Where ``item`` is script
547 specific and ``status`` can be one of ``OK``, ``WARNING``, ``CRITICAL`` or
548 ``UNKNOWN``. Items with status ``WARNING`` or ``CRITICAL`` are logged and
549 annotated in the command line output.
551 .. vim: set textwidth=72 :