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``]
264 | [--hypervisor-state *hvstate*]
265 | [--disk-state *diskstate*]
268 This command changes the role of the node. Each options takes
269 either a literal yes or no, and only one option should be given as
270 yes. The meaning of the roles and flags are described in the
271 manpage **ganeti**(7).
273 The option ``--node-powered`` can be used to modify state-of-record if
274 it doesn't reflect the reality anymore.
276 In case a node is demoted from the master candidate role, the
277 operation will be refused unless you pass the ``--auto-promote``
278 option. This option will cause the operation to lock all cluster nodes
279 (thus it will not be able to run in parallel with most other jobs),
280 but it allows automated maintenance of the cluster candidate pool. If
281 locking all cluster node is too expensive, another option is to
282 promote manually another node to master candidate before demoting the
285 Example (setting a node offline, which will demote it from master
286 candidate role if is in that role)::
288 # gnt-node modify --offline=yes node1.example.com
290 The ``-s (--secondary-ip)`` option can be used to change the node's
291 secondary ip. No drbd instances can be running on the node, while this
292 operation is taking place.
294 Example (setting the node back to online and master candidate)::
296 # gnt-node modify --offline=no --master-candidate=yes node1.example.com
302 **remove** {*nodename*}
304 Removes a node from the cluster. Instances must be removed or
305 migrated to another cluster before.
309 # gnt-node remove node5.example.com
315 **remove-tags** [--from *file*] {*nodename*} {*tag*...}
317 Remove tags from the given node. If any of the tags are not
318 existing on the node, the entire operation will abort.
320 If the ``--from`` option is given, the list of tags to be removed will
321 be extended with the contents of that file (each line becomes a tag).
322 In this case, there is not need to pass tags on the command line (if
323 you do, tags from both sources will be removed). A file name of - will
324 be interpreted as stdin.
329 | **volumes** [--no-headers] [--human-readable]
330 | [--separator=*SEPARATOR*] [{-o|--output} *FIELDS*]
333 Lists all logical volumes and their physical disks from the node(s)
336 The ``--no-headers`` option will skip the initial header line. The
337 ``--separator`` option takes an argument which denotes what will be
338 used between the output fields. Both these options are to help
341 The units used to display the numeric values in the output varies,
342 depending on the options given. By default, the values will be
343 formatted in the most appropriate unit. If the ``--separator``
344 option is given, then the values are shown in mebibytes to allow
345 parsing by scripts. In both cases, the ``--units`` option can be
346 used to enforce a given output unit.
348 The ``-o (--output)`` option takes a comma-separated list of output
349 fields. The available fields and their meaning are:
352 the node name on which the volume exists
355 the physical drive (on which the LVM physical volume lives)
358 the volume group name
361 the logical volume name
364 the logical volume size
367 The name of the instance to which this volume belongs, or (in case
368 it's an orphan volume) the character "-"
373 # gnt-node volumes node5.example.com
374 Node PhysDev VG Name Size Instance
375 node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11000.meta 128 instance1.example.com
376 node1.example.com /dev/hdc1 xenvg instance1.example.com-sda_11001.data 256 instance1.example.com
382 | **list-storage** [--no-headers] [--human-readable]
383 | [--separator=*SEPARATOR*] [--storage-type=*STORAGE\_TYPE*]
384 | [{-o|--output} *FIELDS*]
387 Lists the available storage units and their details for the given
390 The ``--no-headers`` option will skip the initial header line. The
391 ``--separator`` option takes an argument which denotes what will be
392 used between the output fields. Both these options are to help
395 The units used to display the numeric values in the output varies,
396 depending on the options given. By default, the values will be
397 formatted in the most appropriate unit. If the ``--separator``
398 option is given, then the values are shown in mebibytes to allow
399 parsing by scripts. In both cases, the ``--units`` option can be
400 used to enforce a given output unit.
402 The ``--storage-type`` option can be used to choose a storage unit
403 type. Possible choices are lvm-pv, lvm-vg or file.
405 The ``-o (--output)`` option takes a comma-separated list of output
406 fields. The available fields and their meaning are:
409 the node name on which the volume exists
412 the type of the storage unit (currently just what is passed in via
416 the path/identifier of the storage unit
419 total size of the unit; for the file type see a note below
422 used space in the unit; for the file type see a note below
428 whether we the unit is available for allocation (only lvm-pv can
429 change this setting, the other types always report true)
432 Note that for the "file" type, the total disk space might not equal
433 to the sum of used and free, due to the method Ganeti uses to
434 compute each of them. The total and free values are computed as the
435 total and free space values for the filesystem to which the
436 directory belongs, but the used space is computed from the used
437 space under that directory *only*, which might not be necessarily
438 the root of the filesystem, and as such there could be files
439 outside the file storage directory using disk space and causing a
440 mismatch in the values.
444 node1# gnt-node list-storage node2
445 Node Type Name Size Used Free Allocatable
446 node2 lvm-pv /dev/sda7 673.8G 1.5G 672.3G Y
447 node2 lvm-pv /dev/sdb1 698.6G 0M 698.6G Y
453 **modify-storage** [``--allocatable=yes|no``]
454 {*node*} {*storage-type*} {*volume-name*}
456 Modifies storage volumes on a node. Only LVM physical volumes can
457 be modified at the moment. They have a storage type of "lvm-pv".
461 # gnt-node modify-storage --allocatable no node5.example.com lvm-pv /dev/sdb1
467 **repair-storage** [--ignore-consistency] {*node*} {*storage-type*}
470 Repairs a storage volume on a node. Only LVM volume groups can be
471 repaired at this time. They have the storage type "lvm-vg".
473 On LVM volume groups, **repair-storage** runs "vgreduce
478 **Caution:** Running this command can lead to data loss. Use it with
481 The ``--ignore-consistency`` option will ignore any inconsistent
482 disks (on the nodes paired with this one). Use of this option is
483 most likely to lead to data-loss.
487 # gnt-node repair-storage node5.example.com lvm-vg xenvg
493 **powercycle** [``--yes``] [``--force``] {*node*}
495 This command (tries to) forcefully reboot a node. It is a command
496 that can be used if the node environemnt is broken, such that the
497 admin can no longer login over ssh, but the Ganeti node daemon is
500 Note that this command is not guaranteed to work; it depends on the
501 hypervisor how effective is the reboot attempt. For Linux, this
502 command require that the kernel option CONFIG\_MAGIC\_SYSRQ is
505 The ``--yes`` option can be used to skip confirmation, while the
506 ``--force`` option is needed if the target node is the master
512 **power** [``--force``] [``--ignore-status``] [``--all``]
513 [``--power-delay``] on|off|cycle|status [*nodes*]
515 This command calls out to out-of-band management to change the power
516 state of given node. With ``status`` you get the power status as reported
517 by the out-of-band managment script.
519 Note that this command will only work if the out-of-band functionality
520 is configured and enabled on the cluster. If this is not the case,
521 please use the **powercycle** command above.
523 Using ``--force`` you skip the confirmation to do the operation.
524 Currently this only has effect on ``off`` and ``cycle``. On those two
525 you can *not* operate on the master. However, the command will provide
526 you with the command to invoke to operate on the master nerver-mind.
527 This is considered harmful and Ganeti does not support the use of it.
529 Providing ``--ignore-status`` will ignore the offline=N state of a node
530 and continue with power off.
532 ``--power-delay`` specifies the time in seconds (factions allowed)
533 waited between powering on the next node. This is by default 2 seconds
534 but can increased if needed with this option.
536 *nodes* are optional. If not provided it will call out for every node in
537 the cluster. Except for the ``off`` and ``cycle`` command where you've
538 to explicit use ``--all`` to select all.
546 This command calls out to out-of-band management to ask for the health status
547 of all or given nodes. The health contains the node name and then the items
548 element with their status in a ``item=status`` manner. Where ``item`` is script
549 specific and ``status`` can be one of ``OK``, ``WARNING``, ``CRITICAL`` or
550 ``UNKNOWN``. Items with status ``WARNING`` or ``CRITICAL`` are logged and
551 annotated in the command line output.
553 .. vim: set textwidth=72 :