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*]
30 | [\--disk-state *diskstate*]
31 | [\--hypervisor-state *hvstate*]
34 Adds the given node to the cluster.
36 This command is used to join a new node to the cluster. You will
37 have to provide the password for root of the node to be able to add
38 the node in the cluster. The command needs to be run on the Ganeti
41 Note that the command is potentially destructive, as it will
42 forcibly join the specified host the cluster, not paying attention
43 to its current status (it could be already in a cluster, etc.)
45 The ``-s (--secondary-ip)`` is used in dual-home clusters and
46 specifies the new node's IP in the secondary network. See the
47 discussion in **gnt-cluster**(8) for more information.
49 In case you're readding a node after hardware failure, you can use
50 the ``--readd`` parameter. In this case, you don't need to pass the
51 secondary IP again, it will reused from the cluster. Also, the
52 drained and offline flags of the node will be cleared before
55 The ``--force-join`` option is to proceed with adding a node even if it already
56 appears to belong to another cluster. This is used during cluster merging, for
59 The ``-g (--node-group)`` option is used to add the new node into a
60 specific node group, specified by UUID or name. If only one node group
61 exists you can skip this option, otherwise it's mandatory.
63 The ``vm_capable``, ``master_capable``, ``ndparams``, ``diskstate`` and
64 ``hvstate`` options are described in **ganeti**(7), and are used to set
65 the properties of the new node.
67 The command performs some operations that change the state of the master
68 and the new node, like copying certificates and starting the node daemon
69 on the new node, or updating ``/etc/hosts`` on the master node. If the
70 command fails at a later stage, it doesn't undo such changes. This
71 should not be a problem, as a successful run of ``gnt-node add`` will
72 bring everything back in sync.
76 # gnt-node add node5.example.com
77 # gnt-node add -s 192.0.2.5 node5.example.com
78 # gnt-node add -g group2 -s 192.0.2.9 node9.group2.example.com
84 **add-tags** [\--from *file*] {*nodename*} {*tag*...}
86 Add tags to the given node. If any of the tags contains invalid
87 characters, the entire operation will abort.
89 If the ``--from`` option is given, the list of tags will be
90 extended with the contents of that file (each line becomes a tag).
91 In this case, there is not need to pass tags on the command line
92 (if you do, both sources will be used). A file name of - will be
98 **evacuate** [-f] [\--early-release] [\--iallocator *NAME* \|
99 \--new-secondary *destination\_node*]
100 [\--primary-only \| \--secondary-only] [\--early-release] {*node*}
102 This command will move instances away from the given node. If
103 ``--primary-only`` is given, only primary instances are evacuated, with
104 ``--secondary-only`` only secondaries. If neither is given, all
105 instances are evacuated. It works only for instances having a drbd disk
108 The new location for the instances can be specified in two ways:
110 - as a single node for all instances, via the ``-n (--new-secondary)``
113 - or via the ``-I (--iallocator)`` option, giving a script name as
114 parameter, so each instance will be in turn placed on the (per the
117 The ``--early-release`` changes the code so that the old storage on
118 node being evacuated is removed early (before the resync is
119 completed) and the internal Ganeti locks are also released for both
120 the current secondary and the new secondary, thus allowing more
121 parallelism in the cluster operation. This should be used only when
122 recovering from a disk failure on the current secondary (thus the
123 old storage is already broken) or when the storage on the primary
124 node is known to be fine (thus we won't need the old storage for
127 Note that this command is equivalent to using per-instance commands for
128 each affected instance individually:
130 - ``--primary-only`` is equivalent to ``gnt-instance failover/migration``
131 - ``--secondary-only`` is equivalent to ``gnt-instance replace-disks``
132 in the secondary node change mode (only valid for DRBD instances)
133 - when neither of the above is done a combination of the two cases is run
137 # gnt-node evacuate -I hail node3.example.com
143 **failover** [-f] [\--ignore-consistency] {*node*}
145 This command will fail over all instances having the given node as
146 primary to their secondary nodes. This works only for instances having
147 a drbd disk template.
149 Normally the failover will check the consistency of the disks before
150 failing over the instance. If you are trying to migrate instances off
151 a dead node, this will fail. Use the ``--ignore-consistency`` option
156 # gnt-node failover node1.example.com
164 Show detailed information about the nodes in the cluster. If you
165 don't give any arguments, all nodes will be shows, otherwise the
166 output will be restricted to the given names.
172 | [\--no-headers] [\--separator=*SEPARATOR*]
173 | [\--units=*UNITS*] [-v] [{-o|\--output} *[+]FIELD,...*]
177 Lists the nodes in the cluster.
179 The ``--no-headers`` option will skip the initial header line. The
180 ``--separator`` option takes an argument which denotes what will be
181 used between the output fields. Both these options are to help
184 The units used to display the numeric values in the output varies,
185 depending on the options given. By default, the values will be
186 formatted in the most appropriate unit. If the ``--separator``
187 option is given, then the values are shown in mebibytes to allow
188 parsing by scripts. In both cases, the ``--units`` option can be
189 used to enforce a given output unit.
191 Queries of nodes will be done in parallel with any running jobs. This might
192 give inconsistent results for the free disk/memory.
194 The ``-v`` option activates verbose mode, which changes the display of
195 special field states (see **ganeti(7)**).
197 The ``-o (--output)`` option takes a comma-separated list of output
198 fields. The available fields and their meaning are:
202 If the value of the option starts with the character ``+``, the new
203 fields will be added to the default list. This allows one to quickly
204 see the default list plus a few other fields, instead of retyping
205 the entire list of fields.
207 Note that some of these fields are known from the configuration of the
208 cluster (e.g. ``name``, ``pinst``, ``sinst``, ``pip``, ``sip``) and thus
209 the master does not need to contact the node for this data (making the
210 listing fast if only fields from this set are selected), whereas the
211 other fields are "live" fields and require a query to the cluster nodes.
213 Depending on the virtualization type and implementation details, the
214 ``mtotal``, ``mnode`` and ``mfree`` fields may have slighly varying
215 meanings. For example, some solutions share the node memory with the
216 pool of memory used for instances (KVM), whereas others have separate
217 memory for the node and for the instances (Xen).
219 If exactly one argument is given and it appears to be a query filter
220 (see **ganeti(7)**), the query result is filtered accordingly. For
221 ambiguous cases (e.g. a single field name as a filter) the ``--filter``
222 (``-F``) option forces the argument to be treated as a filter (e.g.
223 ``gnt-node list -F master_candidate``).
225 If no node names are given, then all nodes are queried. Otherwise,
226 only the given nodes will be listed.
232 **list-fields** [field...]
234 Lists available fields for nodes.
240 **list-tags** {*nodename*}
242 List the tags of the given node.
247 **migrate** [-f] [\--non-live] [\--migration-mode=live\|non-live]
248 [\--ignore-ipolicy] {*node*}
250 This command will migrate all instances having the given node as
251 primary to their secondary nodes. This works only for instances
252 having a drbd disk template.
254 As for the **gnt-instance migrate** command, the options
255 ``--no-live``, ``--migration-mode`` and ``--no-runtime-changes``
256 can be given to influence the migration type.
258 If ``--ignore-ipolicy`` is given any instance policy violations occuring
259 during this operation are ignored.
263 # gnt-node migrate node1.example.com
269 | **modify** [-f] [\--submit]
270 | [{-C|\--master-candidate} ``yes|no``]
271 | [{-D|\--drained} ``yes|no``] [{-O|\--offline} ``yes|no``]
272 | [\--master-capable=``yes|no``] [\--vm-capable=``yes|no``] [\--auto-promote]
273 | [{-s|\--secondary-ip} *secondary_ip*]
274 | [\--node-parameters *ndparams*]
275 | [\--node-powered=``yes|no``]
276 | [\--hypervisor-state *hvstate*]
277 | [\--disk-state *diskstate*]
280 This command changes the role of the node. Each options takes
281 either a literal yes or no, and only one option should be given as
282 yes. The meaning of the roles and flags are described in the
283 manpage **ganeti**(7).
285 The option ``--node-powered`` can be used to modify state-of-record if
286 it doesn't reflect the reality anymore.
288 In case a node is demoted from the master candidate role, the
289 operation will be refused unless you pass the ``--auto-promote``
290 option. This option will cause the operation to lock all cluster nodes
291 (thus it will not be able to run in parallel with most other jobs),
292 but it allows automated maintenance of the cluster candidate pool. If
293 locking all cluster node is too expensive, another option is to
294 promote manually another node to master candidate before demoting the
297 Example (setting a node offline, which will demote it from master
298 candidate role if is in that role)::
300 # gnt-node modify --offline=yes node1.example.com
302 The ``-s (--secondary-ip)`` option can be used to change the node's
303 secondary ip. No drbd instances can be running on the node, while this
304 operation is taking place.
306 Example (setting the node back to online and master candidate)::
308 # gnt-node modify --offline=no --master-candidate=yes node1.example.com
314 **remove** {*nodename*}
316 Removes a node from the cluster. Instances must be removed or
317 migrated to another cluster before.
321 # gnt-node remove node5.example.com
327 **remove-tags** [\--from *file*] {*nodename*} {*tag*...}
329 Remove tags from the given node. If any of the tags are not
330 existing on the node, the entire operation will abort.
332 If the ``--from`` option is given, the list of tags to be removed will
333 be extended with the contents of that file (each line becomes a tag).
334 In this case, there is not need to pass tags on the command line (if
335 you do, tags from both sources will be removed). A file name of - will
336 be interpreted as stdin.
341 | **volumes** [\--no-headers] [\--human-readable]
342 | [\--separator=*SEPARATOR*] [{-o|\--output} *FIELDS*]
345 Lists all logical volumes and their physical disks from the node(s)
348 The ``--no-headers`` option will skip the initial header line. The
349 ``--separator`` option takes an argument which denotes what will be
350 used between the output fields. Both these options are to help
353 The units used to display the numeric values in the output varies,
354 depending on the options given. By default, the values will be
355 formatted in the most appropriate unit. If the ``--separator``
356 option is given, then the values are shown in mebibytes to allow
357 parsing by scripts. In both cases, the ``--units`` option can be
358 used to enforce a given output unit.
360 The ``-o (--output)`` option takes a comma-separated list of output
361 fields. The available fields and their meaning are:
364 the node name on which the volume exists
367 the physical drive (on which the LVM physical volume lives)
370 the volume group name
373 the logical volume name
376 the logical volume size
379 The name of the instance to which this volume belongs, or (in case
380 it's an orphan volume) the character "-"
385 # gnt-node volumes node5.example.com
386 Node PhysDev VG Name Size Instance
387 node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11000.meta 128 instance1.example.com
388 node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11001.data 256 instance1.example.com
394 | **list-storage** [\--no-headers] [\--human-readable]
395 | [\--separator=*SEPARATOR*] [\--storage-type=*STORAGE\_TYPE*]
396 | [{-o|\--output} *FIELDS*]
399 Lists the available storage units and their details for the given
402 The ``--no-headers`` option will skip the initial header line. The
403 ``--separator`` option takes an argument which denotes what will be
404 used between the output fields. Both these options are to help
407 The units used to display the numeric values in the output varies,
408 depending on the options given. By default, the values will be
409 formatted in the most appropriate unit. If the ``--separator``
410 option is given, then the values are shown in mebibytes to allow
411 parsing by scripts. In both cases, the ``--units`` option can be
412 used to enforce a given output unit.
414 The ``--storage-type`` option can be used to choose a storage unit
415 type. Possible choices are lvm-pv, lvm-vg or file.
417 The ``-o (--output)`` option takes a comma-separated list of output
418 fields. The available fields and their meaning are:
421 the node name on which the volume exists
424 the type of the storage unit (currently just what is passed in via
428 the path/identifier of the storage unit
431 total size of the unit; for the file type see a note below
434 used space in the unit; for the file type see a note below
440 whether we the unit is available for allocation (only lvm-pv can
441 change this setting, the other types always report true)
444 Note that for the "file" type, the total disk space might not equal
445 to the sum of used and free, due to the method Ganeti uses to
446 compute each of them. The total and free values are computed as the
447 total and free space values for the filesystem to which the
448 directory belongs, but the used space is computed from the used
449 space under that directory *only*, which might not be necessarily
450 the root of the filesystem, and as such there could be files
451 outside the file storage directory using disk space and causing a
452 mismatch in the values.
456 node1# gnt-node list-storage node2
457 Node Type Name Size Used Free Allocatable
458 node2 lvm-pv /dev/sda7 673.8G 1.5G 672.3G Y
459 node2 lvm-pv /dev/sdb1 698.6G 0M 698.6G Y
465 **modify-storage** [``--allocatable=yes|no``]
466 {*node*} {*storage-type*} {*volume-name*}
468 Modifies storage volumes on a node. Only LVM physical volumes can
469 be modified at the moment. They have a storage type of "lvm-pv".
473 # gnt-node modify-storage --allocatable no node5.example.com lvm-pv /dev/sdb1
479 **repair-storage** [\--ignore-consistency] {*node*} {*storage-type*}
482 Repairs a storage volume on a node. Only LVM volume groups can be
483 repaired at this time. They have the storage type "lvm-vg".
485 On LVM volume groups, **repair-storage** runs ``vgreduce
490 **Caution:** Running this command can lead to data loss. Use it with
493 The ``--ignore-consistency`` option will ignore any inconsistent
494 disks (on the nodes paired with this one). Use of this option is
495 most likely to lead to data-loss.
499 # gnt-node repair-storage node5.example.com lvm-vg xenvg
505 **powercycle** [``--yes``] [``--force``] {*node*}
507 This command (tries to) forcefully reboot a node. It is a command
508 that can be used if the node environment is broken, such that the
509 admin can no longer login over SSH, but the Ganeti node daemon is
512 Note that this command is not guaranteed to work; it depends on the
513 hypervisor how effective is the reboot attempt. For Linux, this
514 command requires the kernel option ``CONFIG_MAGIC_SYSRQ`` to be
517 The ``--yes`` option can be used to skip confirmation, while the
518 ``--force`` option is needed if the target node is the master
524 **power** [``--force``] [``--ignore-status``] [``--all``]
525 [``--power-delay``] on|off|cycle|status [*nodes*]
527 This command calls out to out-of-band management to change the power
528 state of given node. With ``status`` you get the power status as reported
529 by the out-of-band managment script.
531 Note that this command will only work if the out-of-band functionality
532 is configured and enabled on the cluster. If this is not the case,
533 please use the **powercycle** command above.
535 Using ``--force`` you skip the confirmation to do the operation.
536 Currently this only has effect on ``off`` and ``cycle``. On those two
537 you can *not* operate on the master. However, the command will provide
538 you with the command to invoke to operate on the master nerver-mind.
539 This is considered harmful and Ganeti does not support the use of it.
541 Providing ``--ignore-status`` will ignore the offline=N state of a node
542 and continue with power off.
544 ``--power-delay`` specifies the time in seconds (factions allowed)
545 waited between powering on the next node. This is by default 2 seconds
546 but can increased if needed with this option.
548 *nodes* are optional. If not provided it will call out for every node in
549 the cluster. Except for the ``off`` and ``cycle`` command where you've
550 to explicit use ``--all`` to select all.
558 This command calls out to out-of-band management to ask for the health status
559 of all or given nodes. The health contains the node name and then the items
560 element with their status in a ``item=status`` manner. Where ``item`` is script
561 specific and ``status`` can be one of ``OK``, ``WARNING``, ``CRITICAL`` or
562 ``UNKNOWN``. Items with status ``WARNING`` or ``CRITICAL`` are logged and
563 annotated in the command line output.
565 .. vim: set textwidth=72 :