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gnt-instance(8) Ganeti | Version @GANETI_VERSION@

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Name

----

gnt-instance - Ganeti instance administration

Synopsis

--------

**gnt-instance** {command} [arguments...]

DESCRIPTION

-----------

The **gnt-instance** command is used for instance administration in

the Ganeti system.

COMMANDS

--------

Creation/removal/querying

~~~~~~~~~~~~~~~~~~~~~~~~~

ADD

^^^

| **add**

| {-t {diskless | file \| plain \| drbd}}

| {--disk=*N*: {size=*VAL* \| adopt=*LV*}[,vg=*VG*][,mode=*ro\|rw*]

|  \| -s *SIZE*}

| [--no-ip-check] [--no-name-check] [--no-start] [--no-install]

| [--net=*N* [:options...] \| --no-nics]

| [-B *BEPARAMS*]

| [-H *HYPERVISOR* [: option=*value*... ]]

| [-O, --os-parameters *param*=*value*... ]

| [--file-storage-dir *dir\_path*] [--file-driver {loop \| blktap}]

| {-n *node[:secondary-node]* \| --iallocator *name*}

| {-o *os-type*}

| [--submit]

| {*instance*}

Creates a new instance on the specified host. The *instance* argument

must be in DNS, but depending on the bridge/routing setup, need not be

in the same network as the nodes in the cluster.

The ``disk`` option specifies the parameters for the disks of the

instance. The numbering of disks starts at zero, and at least one disk

needs to be passed. For each disk, either the size or the adoption

source needs to be given, and optionally the access mode (read-only or

the default of read-write) and LVM volume group can also be specified.

The size is interpreted (when no unit is given) in mebibytes. You can

also use one of the suffixes *m*, *g* or *t* to specify the exact the

units used; these suffixes map to mebibytes, gibibytes and tebibytes.

When using the ``adopt`` key in the disk definition, Ganeti will

reuse those volumes (instead of creating new ones) as the

instance's disks. Ganeti will rename these volumes to the standard

format, and (without installing the OS) will use them as-is for the

instance. This allows migrating instances from non-managed mode

(e.q. plain KVM with LVM) to being managed via Ganeti. Note that

this works only for the \`plain' disk template (see below for

template details).

Alternatively, a single-disk instance can be created via the ``-s``

option which takes a single argument, the size of the disk. This is

similar to the Ganeti 1.2 version (but will only create one disk).

The minimum disk specification is therefore ``--disk 0:size=20G`` (or

``-s 20G`` when using the ``-s`` option), and a three-disk instance

can be specified as ``--disk 0:size=20G --disk 1:size=4G --disk

2:size=100G``.

The ``--no-ip-check`` skips the checks that are done to see if the

instance's IP is not already alive (i.e. reachable from the master

node).

The ``--no-name-check`` skips the check for the instance name via

the resolver (e.g. in DNS or /etc/hosts, depending on your setup).

Since the name check is used to compute the IP address, if you pass

this option you must also pass the ``--no-ip-check`` option.

If you don't wat the instance to automatically start after

creation, this is possible via the ``--no-start`` option. This will

leave the instance down until a subsequent **gnt-instance start**

command.

The NICs of the instances can be specified via the ``--net``

option. By default, one NIC is created for the instance, with a

random MAC, and set up according the the cluster level nic

parameters. Each NIC can take these parameters (all optional):

mac

    either a value or 'generate' to generate a new unique MAC

ip

    specifies the IP address assigned to the instance from the Ganeti

    side (this is not necessarily what the instance will use, but what

    the node expects the instance to use)

mode

    specifies the connection mode for this nic: routed or bridged.

link

    in bridged mode specifies the bridge to attach this NIC to, in

    routed mode it's intended to differentiate between different

    routing tables/instance groups (but the meaning is dependent on the

    network script, see gnt-cluster(8) for more details)

Of these "mode" and "link" are nic parameters, and inherit their

default at cluster level.

Alternatively, if no network is desired for the instance, you can

prevent the default of one NIC with the ``--no-nics`` option.

The ``-o`` options specifies the operating system to be installed.

The available operating systems can be listed with **gnt-os list**.

Passing ``--no-install`` will however skip the OS installation,

allowing a manual import if so desired. Note that the

no-installation mode will automatically disable the start-up of the

instance (without an OS, it most likely won't be able to start-up

successfully).

The ``-B`` option specifies the backend parameters for the

instance. If no such parameters are specified, the values are

inherited from the cluster. Possible parameters are:

memory

    the memory size of the instance; as usual, suffixes can be used to

    denote the unit, otherwise the value is taken in mebibites

vcpus

    the number of VCPUs to assign to the instance (if this value makes

    sense for the hypervisor)

auto\_balance

    whether the instance is considered in the N+1 cluster checks

    (enough redundancy in the cluster to survive a node failure)

The ``-H`` option specified the hypervisor to use for the instance

(must be one of the enabled hypervisors on the cluster) and

optionally custom parameters for this instance. If not other

options are used (i.e. the invocation is just -H *NAME*) the

instance will inherit the cluster options. The defaults below show

the cluster defaults at cluster creation time.

The possible hypervisor options are as follows:

boot\_order

    Valid for the Xen HVM and KVM hypervisors.

    A string value denoting the boot order. This has different meaning

    for the Xen HVM hypervisor and for the KVM one.

    For Xen HVM, The boot order is a string of letters listing the boot

    devices, with valid device letters being:

    a

        floppy drive

    c

        hard disk

    d

        CDROM drive

    n

        network boot (PXE)

    The default is not to set an HVM boot order which is interpreted as

    'dc'.

    For KVM the boot order is either "cdrom", "disk" or "network".

    Please note that older versions of KVM couldn't netboot from virtio

    interfaces. This has been fixed in more recent versions and is

    confirmed to work at least with qemu-kvm 0.11.1.

blockdev\_prefix

    Valid for the Xen HVM and PVM hypervisors.

    Relevant to nonpvops guest kernels, in which the disk device names are

    given by the host.  Allows to specify 'xvd', which helps run Red Hat based

    installers, driven by anaconda.

cdrom\_image\_path

    Valid for the Xen HVM and KVM hypervisors.

    The path to a CDROM image to attach to the instance.

nic\_type

    Valid for the Xen HVM and KVM hypervisors.

    This parameter determines the way the network cards are presented

    to the instance. The possible options are:

    rtl8139 (default for Xen HVM) (HVM & KVM)

    ne2k\_isa (HVM & KVM)

    ne2k\_pci (HVM & KVM)

    i82551 (KVM)

    i82557b (KVM)

    i82559er (KVM)

    pcnet (KVM)

    e1000 (KVM)

    paravirtual (default for KVM) (HVM & KVM)

disk\_type

    Valid for the Xen HVM and KVM hypervisors.

    This parameter determines the way the disks are presented to the

    instance. The possible options are:

    ioemu (default for HVM & KVM) (HVM & KVM)

    ide (HVM & KVM)

    scsi (KVM)

    sd (KVM)

    mtd (KVM)

    pflash (KVM)

vnc\_bind\_address

    Valid for the Xen HVM and KVM hypervisors.

    Specifies the address that the VNC listener for this instance

    should bind to. Valid values are IPv4 addresses. Use the address

    0.0.0.0 to bind to all available interfaces (this is the default)

    or specify the address of one of the interfaces on the node to

    restrict listening to that interface.

vnc\_tls

    Valid for the KVM hypervisor.

    A boolean option that controls whether the VNC connection is

    secured with TLS.

vnc\_x509\_path

    Valid for the KVM hypervisor.

    If ``vnc_tls`` is enabled, this options specifies the path to the

    x509 certificate to use.

vnc\_x509\_verify

    Valid for the KVM hypervisor.

acpi

    Valid for the Xen HVM and KVM hypervisors.

    A boolean option that specifies if the hypervisor should enable

    ACPI support for this instance. By default, ACPI is disabled.

pae

    Valid for the Xen HVM and KVM hypervisors.

    A boolean option that specifies if the hypervisor should enabled

    PAE support for this instance. The default is false, disabling PAE

    support.

use\_localtime

    Valid for the Xen HVM and KVM hypervisors.

    A boolean option that specifies if the instance should be started

    with its clock set to the localtime of the machine (when true) or

    to the UTC (When false). The default is false, which is useful for

    Linux/Unix machines; for Windows OSes, it is recommended to enable

    this parameter.

kernel\_path

    Valid for the Xen PVM and KVM hypervisors.

    This option specifies the path (on the node) to the kernel to boot

    the instance with. Xen PVM instances always require this, while for

    KVM if this option is empty, it will cause the machine to load the

    kernel from its disks.

kernel\_args

    Valid for the Xen PVM and KVM hypervisors.

    This options specifies extra arguments to the kernel that will be

    loaded. device. This is always used for Xen PVM, while for KVM it

    is only used if the ``kernel_path`` option is also specified.

    The default setting for this value is simply ``"ro"``, which mounts

    the root disk (initially) in read-only one. For example, setting

    this to single will cause the instance to start in single-user

    mode.

initrd\_path

    Valid for the Xen PVM and KVM hypervisors.

    This option specifies the path (on the node) to the initrd to boot

    the instance with. Xen PVM instances can use this always, while for

    KVM if this option is only used if the ``kernel_path`` option is

    also specified. You can pass here either an absolute filename (the

    path to the initrd) if you want to use an initrd, or use the format

    no\_initrd\_path for no initrd.

root\_path

    Valid for the Xen PVM and KVM hypervisors.

    This options specifies the name of the root device. This is always

    needed for Xen PVM, while for KVM it is only used if the

    ``kernel_path`` option is also specified.

serial\_console

    Valid for the KVM hypervisor.

    This boolean option specifies whether to emulate a serial console

    for the instance.

disk\_cache

    Valid for the KVM hypervisor.

    The disk cache mode. It can be either default to not pass any cache

    option to KVM, or one of the KVM cache modes: none (for direct

    I/O), writethrough (to use the host cache but report completion to

    the guest only when the host has committed the changes to disk) or

    writeback (to use the host cache and report completion as soon as

    the data is in the host cache). Note that there are special

    considerations for the cache mode depending on version of KVM used

    and disk type (always raw file under Ganeti), please refer to the

    KVM documentation for more details.

security\_model

    Valid for the KVM hypervisor.

    The security model for kvm. Currently one of "none", "user" or

    "pool". Under "none", the default, nothing is done and instances

    are run as the Ganeti daemon user (normally root).

    Under "user" kvm will drop privileges and become the user specified

    by the security\_domain parameter.

    Under "pool" a global cluster pool of users will be used, making

    sure no two instances share the same user on the same node. (this

    mode is not implemented yet)

security\_domain

    Valid for the KVM hypervisor.

    Under security model "user" the username to run the instance under.

    It must be a valid username existing on the host.

    Cannot be set under security model "none" or "pool".

kvm\_flag

    Valid for the KVM hypervisor.

    If "enabled" the -enable-kvm flag is passed to kvm. If "disabled"

    -disable-kvm is passed. If unset no flag is passed, and the default

    running mode for your kvm binary will be used.

mem\_path

    Valid for the KVM hypervisor.

    This option passes the -mem-path argument to kvm with the path (on

    the node) to the mount point of the hugetlbfs file system, along

    with the -mem-prealloc argument too.

use\_chroot

    Valid for the KVM hypervisor.

    This boolean option determines wether to run the KVM instance in a

    chroot directory.

    If it is set to ``true``, an empty directory is created before

    starting the instance and its path is passed via the -chroot flag

    to kvm. The directory is removed when the instance is stopped.

    It is set to ``false`` by default.

migration\_downtime

    Valid for the KVM hypervisor.

    The maximum amount of time (in ms) a KVM instance is allowed to be

    frozen during a live migration, in order to copy dirty memory

    pages. Default value is 30ms, but you may need to increase this

    value for busy instances.

    This option is only effective with kvm versions >= 87 and qemu-kvm

    versions >= 0.11.0.

cpu\_mask

    Valid for the LXC hypervisor.

    The processes belonging to the given instance are only scheduled on

    the specified CPUs.

    The parameter format is a comma-separated list of CPU IDs or CPU ID

    ranges. The ranges are defined by a lower and higher boundary,

    separated by a dash. The boundaries are inclusive.

usb\_mouse

    Valid for the KVM hypervisor.

    This option specifies the usb mouse type to be used. It can be

    "mouse" or "tablet". When using VNC it's recommended to set it to

    "tablet".

The ``-O`` (``--os-parameters``) option allows customisation of the OS

parameters. The actual parameter names and values depends on the OS

being used, but the syntax is the same key=value. For example, setting

a hypothetical ``dhcp`` parameter to yes can be achieved by::

    gnt-instance add -O dhcp=yes ...

The ``--iallocator`` option specifies the instance allocator plugin

to use. If you pass in this option the allocator will select nodes

for this instance automatically, so you don't need to pass them

with the ``-n`` option. For more information please refer to the

instance allocator documentation.

The ``-t`` options specifies the disk layout type for the instance.

The available choices are:

diskless

    This creates an instance with no disks. Its useful for testing only

    (or other special cases).

file

    Disk devices will be regular files.

plain

    Disk devices will be logical volumes.

drbd

    Disk devices will be drbd (version 8.x) on top of lvm volumes.

The optional second value of the ``--node`` is used for the drbd

template type and specifies the remote node.

If you do not want gnt-instance to wait for the disk mirror to be

synced, use the ``--no-wait-for-sync`` option.

The ``--file-storage-dir`` specifies the relative path under the

cluster-wide file storage directory to store file-based disks. It is

useful for having different subdirectories for different

instances. The full path of the directory where the disk files are

stored will consist of cluster-wide file storage directory + optional

subdirectory + instance name. Example:

``@RPL_FILE_STORAGE_DIR@``*/mysubdir/instance1.example.com*. This

option is only relevant for instances using the file storage backend.

The ``--file-driver`` specifies the driver to use for file-based

disks. Note that currently these drivers work with the xen

hypervisor only. This option is only relevant for instances using

the file storage backend. The available choices are:

loop

    Kernel loopback driver. This driver uses loopback devices to access

    the filesystem within the file. However, running I/O intensive

    applications in your instance using the loop driver might result in

    slowdowns. Furthermore, if you use the loopback driver consider

    increasing the maximum amount of loopback devices (on most systems

    it's 8) using the max\_loop param.

blktap

    The blktap driver (for Xen hypervisors). In order to be able to use

    the blktap driver you should check if the 'blktapctrl' user space

    disk agent is running (usually automatically started via xend).

    This user-level disk I/O interface has the advantage of better

    performance. Especially if you use a network file system (e.g. NFS)

    to store your instances this is the recommended choice.

The ``--submit`` option is used to send the job to the master

daemon but not wait for its completion. The job ID will be shown so

that it can be examined via **gnt-job info**.

Example::

    # gnt-instance add -t file --disk 0:size=30g -B memory=512 -o debian-etch \

      -n node1.example.com --file-storage-dir=mysubdir instance1.example.com

    # gnt-instance add -t plain --disk 0:size=30g -B memory=512 -o debian-etch \

      -n node1.example.com instance1.example.com

    # gnt-instance add -t plain --disk 0:size=30g --disk 1:size=100g,vg=san \

      -B memory=512 -o debian-etch -n node1.example.com instance1.example.com

    # gnt-instance add -t drbd --disk 0:size=30g -B memory=512 -o debian-etch \

      -n node1.example.com:node2.example.com instance2.example.com

BATCH-CREATE

^^^^^^^^^^^^

**batch-create** {instances\_file.json}

This command (similar to the Ganeti 1.2 **batcher** tool) submits

multiple instance creation jobs based on a definition file. The

instance configurations do not encompass all the possible options

for the **add** command, but only a subset.

The instance file should be a valid-formed JSON file, containing a

dictionary with instance name and instance parameters. The accepted

parameters are:

disk\_size

    The size of the disks of the instance.

disk\_template

    The disk template to use for the instance, the same as in the

    **add** command.

backend

    A dictionary of backend parameters.

hypervisor

    A dictionary with a single key (the hypervisor name), and as value

    the hypervisor options. If not passed, the default hypervisor and

    hypervisor options will be inherited.

mac, ip, mode, link

    Specifications for the one NIC that will be created for the

    instance. 'bridge' is also accepted as a backwards compatibile

    key.

nics

    List of nics that will be created for the instance. Each entry

    should be a dict, with mac, ip, mode and link as possible keys.

    Please don't provide the "mac, ip, mode, link" parent keys if you

    use this method for specifying nics.

primary\_node, secondary\_node

    The primary and optionally the secondary node to use for the

    instance (in case an iallocator script is not used).

iallocator

    Instead of specifying the nodes, an iallocator script can be used

    to automatically compute them.

start

    whether to start the instance

ip\_check

    Skip the check for already-in-use instance; see the description in

    the **add** command for details.

name\_check

    Skip the name check for instances; see the description in the

    **add** command for details.

file\_storage\_dir, file\_driver

    Configuration for the file disk type, see the **add** command for

    details.

A simple definition for one instance can be (with most of the

parameters taken from the cluster defaults)::

    {

      "instance3": {

        "template": "drbd",

        "os": "debootstrap",

        "disk_size": ["25G"],

        "iallocator": "dumb"

      },

      "instance5": {

        "template": "drbd",

        "os": "debootstrap",

        "disk_size": ["25G"],

        "iallocator": "dumb",

        "hypervisor": "xen-hvm",

        "hvparams": {"acpi": true},

        "backend": {"memory": 512}

      }

    }

The command will display the job id for each submitted instance, as

follows::

    # gnt-instance batch-create instances.json

    instance3: 11224

    instance5: 11225

REMOVE

^^^^^^

**remove** [--ignore-failures] [--shutdown-timeout=*N*] [--submit]

{*instance*}

Remove an instance. This will remove all data from the instance and

there is *no way back*. If you are not sure if you use an instance

again, use **shutdown** first and leave it in the shutdown state

for a while.

The ``--ignore-failures`` option will cause the removal to proceed

even in the presence of errors during the removal of the instance

(e.g. during the shutdown or the disk removal). If this option is

not given, the command will stop at the first error.

The ``--shutdown-timeout`` is used to specify how much time to wait

before forcing the shutdown (e.g. ``xm destroy`` in Xen, killing the

kvm process for KVM, etc.). By default two minutes are given to each

instance to stop.

The ``--submit`` option is used to send the job to the master

daemon but not wait for its completion. The job ID will be shown so

that it can be examined via **gnt-job info**.

Example::

    # gnt-instance remove instance1.example.com

LIST

^^^^

| **list**

| [--no-headers] [--separator=*SEPARATOR*] [--units=*UNITS*] [-v]

| [-o *[+]FIELD,...*] [instance...]

Shows the currently configured instances with memory usage, disk

usage, the node they are running on, and their run status.

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 ``-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.

The available fields and their meaning are:

name

    the instance name

os

    the OS of the instance

pnode

    the primary node of the instance

snodes

    comma-separated list of secondary nodes for the instance; usually

    this will be just one node

admin\_state

    the desired state of the instance (either "yes" or "no" denoting

    the instance should run or not)

disk\_template

    the disk template of the instance

oper\_state

    the actual state of the instance; can be one of the values

    "running", "stopped", "(node down)"

status

    combined form of ``admin_state`` and ``oper_stat``; this can be one of:

    ``ERROR_nodedown`` if the node of the instance is down, ``ERROR_down`` if

    the instance should run but is down, ``ERROR_up`` if the instance should be

    stopped but is actually running, ``ERROR_wrongnode`` if the instance is

    running but not on the primary, ``ADMIN_down`` if the instance has been

    stopped (and is stopped) and ``running`` if the instance is set to be

    running (and is running)

oper\_ram

    the actual memory usage of the instance as seen by the hypervisor

oper\_vcpus

    the actual number of VCPUs the instance is using as seen by the

    hypervisor

ip

    the ip address Ganeti recognizes as associated with the first

    instance interface

mac

    the first instance interface MAC address

nic\_mode

    the mode of the first instance NIC (routed or bridged)

nic\_link

    the link of the first instance NIC

sda\_size

    the size of the instance's first disk

sdb\_size

    the size of the instance's second disk, if any

vcpus

    the number of VCPUs allocated to the instance

tags

    comma-separated list of the instances's tags

serial\_no

    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 track modifications

ctime

    the creation time of the instance; note that this field contains

    spaces and as such it's harder to parse

    if this attribute is not present (e.g. when upgrading from older

    versions), then "N/A" will be shown instead

mtime

    the last modification time of the instance; note that this field

    contains spaces and as such it's harder to parse

    if this attribute is not present (e.g. when upgrading from older

    versions), then "N/A" will be shown instead

uuid

    Show the UUID of the instance (generated automatically by Ganeti)

network\_port

    If the instance has a network port assigned to it (e.g. for VNC

    connections), this will be shown, otherwise - will be displayed.

beparams

    A text format of the entire beparams for the instance. It's more

    useful to select individual fields from this dictionary, see

    below.

disk.count

    The number of instance disks.

disk.size/N

    The size of the instance's Nth disk. This is a more generic form of

    the sda\_size and sdb\_size fields.

disk.sizes

    A comma-separated list of the disk sizes for this instance.

disk\_usage

    The total disk space used by this instance on each of its nodes.

    This is not the instance-visible disk size, but the actual disk

    "cost" of the instance.

nic.mac/N

    The MAC of the Nth instance NIC.

nic.ip/N

    The IP address of the Nth instance NIC.

nic.mode/N

    The mode of the Nth instance NIC

nic.link/N

    The link of the Nth instance NIC

nic.macs

    A comma-separated list of all the MACs of the instance's NICs.

nic.ips

    A comma-separated list of all the IP addresses of the instance's

    NICs.

nic.modes

    A comma-separated list of all the modes of the instance's NICs.

nic.links

    A comma-separated list of all the link parameters of the instance's

    NICs.

nic.count

    The number of instance nics.

hv/*NAME*

    The value of the hypervisor parameter called *NAME*. For details of

    what hypervisor parameters exist and their meaning, see the **add**

    command.

be/memory

    The configured memory for the instance.

be/vcpus

    The configured number of VCPUs for the instance.

be/auto\_balance

    Whether the instance is considered in N+1 checks.

If the value of the option starts with the character ``+``, the new

field(s) 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.

There is a subtle grouping about the available output fields: all

fields except for ``oper_state``, ``oper_ram``, ``oper_vcpus`` and

``status`` are configuration value and not run-time values. So if

you don't select any of the these fields, the query will be

satisfied instantly from the cluster configuration, without having

to ask the remote nodes for the data. This can be helpful for big

clusters when you only want some data and it makes sense to specify

a reduced set of output fields.

The default output field list is: name, os, pnode, admin\_state,

oper\_state, oper\_ram.

LIST-FIELDS

~~~~~~~~~~

**list-fields** [field...]

Lists available fields for instances.

INFO

^^^^

**info** [-s \| --static] [--roman] {--all \| *instance*}

Show detailed information about the given instance(s). This is

different from **list** as it shows detailed data about the

instance's disks (especially useful for the drbd disk template).

If the option ``-s`` is used, only information available in the

configuration file is returned, without querying nodes, making the

operation faster.

Use the ``--all`` to get info about all instances, rather than

explicitly passing the ones you're interested in.

The ``--roman`` option can be used to cause envy among people who

like ancient cultures, but are stuck with non-latin-friendly

cluster virtualization technologies.

MODIFY

^^^^^^

| **modify**

| [-H *HYPERVISOR\_PARAMETERS*]

| [-B *BACKEND\_PARAMETERS*]

| [--net add*[:options]* \| --net remove \| --net *N:options*]

| [--disk add:size=*SIZE*[,vg=*VG*] \| --disk remove \|

|  --disk *N*:mode=*MODE*]

| [-t plain | -t drbd -n *new_secondary*]

| [--os-type=*OS* [--force-variant]]

| [-O, --os-parameters *param*=*value*... ]

| [--submit]

| {*instance*}

Modifies the memory size, number of vcpus, ip address, MAC address

and/or nic parameters for an instance. It can also add and remove

disks and NICs to/from the instance. Note that you need to give at

least one of the arguments, otherwise the command complains.

The ``-H``, ``-B`` and ``-O`` options specifies hypervisor, backend

and OS parameter options in the form of name=value[,...]. For details

which options can be specified, see the **add** command.

The ``-t`` option will change the disk template of the instance.

Currently only conversions between the plain and drbd disk templates

are supported, and the instance must be stopped before attempting the

conversion. When changing from the plain to the drbd disk template, a

new secondary node must be specified via the ``-n`` option.

The ``--disk add:size=``*SIZE* option adds a disk to the instance. The

optional ``vg=``*VG* option specifies LVM volume group other than default

vg to create disk on. The ``--disk remove`` option will remove the last

disk of the instance. The ``--disk`` *N*``:mode=``*MODE* option will change

the mode of the Nth disk of the instance between read-only (``ro``) and

read-write (``rw``).

The ``--net add:``*options* option will add a new NIC to the

instance. The available options are the same as in the **add** command

(mac, ip, link, mode). The ``--net remove`` will remove the last NIC

of the instance, while the ``--net`` *N*:*options* option will

change the parameters of the Nth instance NIC.

The option ``--os-type`` will change the OS name for the instance

(without reinstallation). In case an OS variant is specified that

is not found, then by default the modification is refused, unless

``--force-variant`` is passed. An invalid OS will also be refused,

unless the ``--force`` option is given.

The ``--submit`` option is used to send the job to the master

daemon but not wait for its completion. The job ID will be shown so

that it can be examined via **gnt-job info**.

All the changes take effect at the next restart. If the instance is

running, there is no effect on the instance.

REINSTALL

^^^^^^^^^

| **reinstall** [-o *os-type*] [--select-os] [-f *force*]

| [--force-multiple]

| [--instance \| --node \| --primary \| --secondary \| --all]

| [-O *OS\_PARAMETERS*] [--submit] {*instance*...}

Reinstalls the operating system on the given instance(s). The

instance(s) must be stopped when running this command. If the

``--os-type`` is specified, the operating system is changed.

The ``--select-os`` option switches to an interactive OS reinstall.

The user is prompted to select the OS template from the list of

available OS templates. OS parameters can be overridden using ``-O``

(more documentation for this option under the **add** command).

Since this is a potentially dangerous command, the user will be

required to confirm this action, unless the ``-f`` flag is passed.

When multiple instances are selected (either by passing multiple

arguments or by using the ``--node``, ``--primary``,

``--secondary`` or ``--all`` options), the user must pass the

``--force-multiple`` options to skip the interactive confirmation.

The ``--submit`` option is used to send the job to the master

daemon but not wait for its completion. The job ID will be shown so

that it can be examined via **gnt-job info**.

RENAME

^^^^^^

| **rename** [--no-ip-check] [--no-name-check] [--submit]

| {*instance*} {*new\_name*}

Renames the given instance. The instance must be stopped when

running this command. The requirements for the new name are the

same as for adding an instance: the new name must be resolvable and

the IP it resolves to must not be reachable (in order to prevent

duplicate IPs the next time the instance is started). The IP test

can be skipped if the ``--no-ip-check`` option is passed.

The ``--no-name-check`` skips the check for the new instance name

via the resolver (e.g. in DNS or /etc/hosts, depending on your

setup). Since the name check is used to compute the IP address, if

you pass this option you must also pass the ``--no-ip-check``

option.

The ``--submit`` option is used to send the job to the master

daemon but not wait for its completion. The job ID will be shown so

that it can be examined via **gnt-job info**.

Starting/stopping/connecting to console

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

STARTUP