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gnt-instance

NAME

gnt-instance - ganeti instance administration

SYNOPSIS

gnt-instance command [ arguments... ]

DESCRIPTION

The gnt-instance 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 },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 ... ] ]
    [ --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) 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 specificy 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.

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.

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: /srv/ganeti/file-storage/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 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_templace

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 (xm destroy in xen, killing the kvm process, for kvm). 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 ] [ -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 -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, 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

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 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.

INFO

info [ -s | --static ] { --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.

MODIFY

modify
    [ -H HYPERVISOR_PARAMETERS ]
    [ -B BACKEND_PARAMETERS ]
    [ --net add[:options] | --net remove | --net N:options ]
    [ --disk add:size=SIZE | --disk remove | --disk N:mode=MODE ]
    [ -t { plain | drbd } ]
    [ --os-name=OS  [ --force-variant ] ]
    [ --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 option specifies hypervisor 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.

The --disk add:size=SIZE option adds a disk to the instance. The --disk remove 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-name 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 ] [ --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.

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 both the --force and --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 ] [ --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 --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

startup
    [ --force ]
    [ --force-multiple ]
    [ --instance | --node | --primary | --secondary | --all | --tags | --node-tags | --pri-node-tags | --sec-node-tags ]
    [ -H key=value... ] [ -B key=value... ]
    [ --submit ]
    [ name ... ]

Starts one or more instances, depending on the following options. The four available modes are:

--instance

will start the instances given as arguments (at least one argument required); this is the default selection

--node

will start the instances who have the given node as either primary or secondary

--primary

will start all instances whose primary node is in the list of nodes passed as arguments (at least one node required)

--secondary

will start all instances whose secondary node is in the list of nodes passed as arguments (at least one node required)

--all

will start all instances in the cluster (no arguments accepted)

--tags

will start all instances in the cluster with the tags given as arguments

--node-tags

will start all instances in the cluster on nodes with the tags given as arguments

--pri-node-tags

will start all instances in the cluster on primary nodes with the tags given as arguments

--sec-node-tags

will start all instances in the cluster on secondary nodes with the tags given as arguments

Note that although you can pass more than one selection option, the last one wins, so in order to guarantee the desired result, don't pass more than one such option.

Use --force to start even if secondary disks are failing.

The --force-multiple will skip the interactive confirmation in the case the more than one instance will be affected.

The -H and -B options specify temporary hypervisor and backend parameters that can be used to start an instance with modified parameters. They can be useful for quick testing without having to modify an instance back and forth, e.g.:

 # gnt-instance start -H root_args="single" instance1
 # gnt-instance start -B memory=2048 instance2
           
 

The first form will start the instance instance1 in single-user mode, and the instance instance2 with 2GB of RAM (this time only, unless that is the actual instance memory size already). Note that the values override the instance parameters (and not extend them): an instance with "root_args=ro" when started with -H root_args=single will result in "single", not "ro single".

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 start instance1.example.com
 # gnt-instance start --node node1.example.com node2.example.com
 # gnt-instance start --all
           
 

SHUTDOWN

shutdown
    [ --timeout=N ]
    [ --force-multiple ]
    [ --instance | --node | --primary | --secondary | --all | --tags | --node-tags | --pri-node-tags | --sec-node-tags ]
    [ --submit ]
    [ name ... ]

Stops one or more instances. If the instance cannot be cleanly stopped during a hardcoded interval (currently 2 minutes), it will forcibly stop the instance (equivalent to switching off the power on a physical machine).

The --timeout is used to specify how much time to wait before forcing the shutdown (xm destroy in xen, killing the kvm process, for kvm). By default two minutes are given to each instance to stop.

The --instance, --node, --primary, --secondary, --all, --tags, --node-tags, --pri-node-tags and --sec-node-tags options are similar as for the startup command and they influence the actual instances being shutdown.

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 shutdown instance1.example.com
 # gnt-instance shutdown --all
           
 

REBOOT

reboot
    [ --type=REBOOT-TYPE ]
    [ --ignore-secondaries ]
    [ --shutdown-timeout=N ]
    [ --force-multiple ]
    [ --instance | --node | --primary | --secondary | --all | --tags | --node-tags | --pri-node-tags | --sec-node-tags ]
    [ --submit ]
    [ name ... ]

Reboots one or more instances. The type of reboot depends on the value of --type. A soft reboot does a hypervisor reboot, a hard reboot does a instance stop, recreates the hypervisor config for the instance and starts the instance. A full reboot does the equivalent of gnt-instance shutdown && gnt-instance startup. The default is hard reboot.

For the hard reboot the option --ignore-secondaries ignores errors for the secondary node while re-assembling the instance disks.

The --instance, --node, --primary, --secondary, --all, --tags, --node-tags, --pri-node-tags and --sec-node-tags options are similar as for the startup command and they influence the actual instances being rebooted.

The --shutdown-timeout is used to specify how much time to wait before forcing the shutdown (xm destroy in xen, killing the kvm process, for kvm). By default two minutes are given to each instance to stop.

The --force-multiple will skip the interactive confirmation in the case the more than one instance will be affected.

Example:

 # gnt-instance reboot instance1.example.com
 # gnt-instance reboot --type=full instance1.example.com
           
 

CONSOLE

console [ --show-cmd ] instance

Connects to the console of the given instance. If the instance is not up, an error is returned. Use the --show-cmd option to display the command instead of executing it.

For HVM instances, this will attempt to connect to the serial console of the instance. To connect to the virtualized "physical" console of a HVM instance, use a VNC client with the connection info from the info command.

Example:

 # gnt-instance console instance1.example.com
           
 

DISK MANAGEMENT

REPLACE-DISKS

replace-disks [ --submit ] [ --early-release ] -p [ --disks idx ] instance

replace-disks [ --submit ] [ --early-release ] -s [ --disks idx ] instance

replace-disks [ --submit ] [ --early-release ] { --iallocator name | --new-secondary NODE } instance

replace-disks [ --submit ] [ --early-release ] --auto instance

This command is a generalized form for replacing disks. It is currently only valid for the mirrored (DRBD) disk template.

The first form (when passing the -p option) will replace the disks on the primary, while the second form (when passing the -s option will replace the disks on the secondary node. For these two cases (as the node doesn't change), it is possible to only run the replace for a subset of the disks, using the option --disks which takes a list of comma-delimited disk indices (zero-based), e.g. 0,2 to replace only the first and third disks.

The third form (when passing either the --iallocator or the --new-secondary option) is designed to change secondary node of the instance. Specifying --iallocator makes the new secondary be selected automatically by the specified allocator plugin, otherwise the new secondary node will be the one chosen manually via the --new-secondary option.

The fourth form (when using --auto) will automatically determine which disks of an instance are faulty and replace them within the same node. The --auto option works only when an instance has only faulty disks on either the primary or secondary node; it doesn't work when both sides have faulty disks.

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.

The --early-release changes the code so that the old storage on secondary node(s) is removed early (before the resync is completed) and the internal Ganeti locks for the current (and new, if any) secondary node are also released, thus allowing more parallelism in the cluster operation. This should be used only when recovering from a disk failure on the current secondary (thus the old storage is already broken) or when the storage on the primary node is known to be fine (thus we won't need the old storage for potential recovery).

Note that it is not possible to select an offline or drained node as a new secondary.

ACTIVATE-DISKS

activate-disks [ --submit ] [ --ignore-size ] instance

Activates the block devices of the given instance. If successful, the command will show the location and name of the block devices:

 node1.example.com:disk/0:/dev/drbd0
 node1.example.com:disk/1:/dev/drbd1
           
 

In this example, node1.example.com is the name of the node on which the devices have been activated. The disk/0 and disk/1 are the Ganeti-names of the instance disks; how they are visible inside the instance is hypervisor-specific. /dev/drbd0 and /dev/drbd1 are the actual block devices as visible on the node.

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.

The --ignore-size option can be used to activate disks ignoring the currently configured size in Ganeti. This can be used in cases where the configuration has gotten out of sync with the real-world (e.g. after a partially-failed grow-disk operation or due to rounding in LVM devices). This should not be used in normal cases, but only when activate-disks fails without it.

Note that it is safe to run this command while the instance is already running.

DEACTIVATE-DISKS

deactivate-disks [ --submit ] instance

De-activates the block devices of the given instance. Note that if you run this command for an instance with a drbd disk template, while it is running, it will not be able to shutdown the block devices on the primary node, but it will shutdown the block devices on the secondary nodes, thus breaking the replication.

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.

GROW-DISK

grow-disk [ --no-wait-for-sync ] [ --submit ] instance disk amount

Grows an instance's disk. This is only possible for instances having a plain or drbd disk template.

Note that this command only change the block device size; it will not grow the actual filesystems, partitions, etc. that live on that disk. Usually, you will need to:

1.

use gnt-instance grow-disk

2.

reboot the instance (later, at a convenient time)

3.

use a filesystem resizer, such as ext2online(8) or xfs_growfs(8) to resize the filesystem, or use fdisk(8) to change the partition table on the disk

The disk argument is the index of the instance disk to grow. The amount argument is given either as a number (and it represents the amount to increase the disk with in mebibytes) or can be given similar to the arguments in the create instance operation, with a suffix denoting the unit.

Note that the disk grow operation might complete on one node but fail on the other; this will leave the instance with different-sized LVs on the two nodes, but this will not create problems (except for unused space).

If you do not want gnt-instance to wait for the new disk region to be synced, use the --no-wait-for-sync 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.

Example (increase the first disk for instance1 by 16GiB):

 # gnt-instance grow-disk instance1.example.com 0 16g
           
 

Also note that disk shrinking is not supported; use gnt-backup export and then gnt-backup import to reduce the disk size of an instance.

RECREATE-DISKS

recreate-disks [ --submit ] [ --disks=indices ] instance

Recreates the disks of the given instance, or only a subset of the disks (if the option disks is passed, which must be a comma-separated list of disk indices, starting from zero).

Note that this functionality should only be used for missing disks; if any of the given disks already exists, the operation will fail. While this is suboptimal, recreate-disks should hopefully not be needed in normal operation and as such the impact of this is low.

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.

RECOVERY

FAILOVER

failover [ -f ] [ --ignore-consistency ] [ --shutdown-timeout=N ] [ --submit ] instance

Failover will fail the instance over its secondary node. 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. Note that this option can be dangerous as errors in shutting down the instance will be ignored, resulting in possibly having the instance running on two machines in parallel (on disconnected DRBD drives).

The --shutdown-timeout is used to specify how much time to wait before forcing the shutdown (xm destroy in xen, killing the kvm process, for kvm). 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 failover instance1.example.com
           
 

MIGRATE

migrate [ -f ] --cleanup instance

migrate [ -f ] [ --non-live ] instance

Migrate will move the instance to its secondary node without shutdown. It only works for instances having the drbd8 disk template type.

The migration command needs a perfectly healthy instance, as we rely on the dual-master capability of drbd8 and the disks of the instance are not allowed to be degraded.

The --non-live option will switch (for the hypervisors that support it) between a "fully live" (i.e. the interruption is as minimal as possible) migration and one in which the instance is frozen, its state saved and transported to the remote node, and then resumed there. This all depends on the hypervisor support for two different methods. In any case, it is not an error to pass this parameter (it will just be ignored if the hypervisor doesn't support it).

If the --cleanup option is passed, the operation changes from migration to attempting recovery from a failed previous migration. In this mode, ganeti checks if the instance runs on the correct node (and updates its configuration if not) and ensures the instances's disks are configured correctly. In this mode, the --non-live option is ignored.

The option -f will skip the prompting for confirmation.

Example (and expected output):

 # gnt-instance migrate instance1
 Migrate will happen to the instance instance1. Note that migration is
 **experimental** in this version. This might impact the instance if
 anything goes wrong. Continue?
 y/[n]/?: y
 * checking disk consistency between source and target
 * ensuring the target is in secondary mode
 * changing disks into dual-master mode
  - INFO: Waiting for instance instance1 to sync disks.
  - INFO: Instance instance1's disks are in sync.
 * migrating instance to node2.example.com
 * changing the instance's disks on source node to secondary
  - INFO: Waiting for instance instance1 to sync disks.
  - INFO: Instance instance1's disks are in sync.
 * changing the instance's disks to single-master
 #
           
 

MOVE

move [ -f ] [ -n node ] [ --shutdown-timeout=N ] [ --submit ] instance

Move will move the instance to an arbitrary node in the cluster. This works only for instances having a plain or file disk template.

Note that since this operation is done via data copy, it will take a long time for big disks (similar to replace-disks for a drbd instance).

The --shutdown-timeout is used to specify how much time to wait before forcing the shutdown (xm destroy in xen, killing the kvm process, for kvm). 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 move -n node3.example.com instance1.example.com
           
 

TAGS

ADD-TAGS

add-tags [ --from file ] instancename tag ...

Add tags to the given instance. 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.

LIST-TAGS

list-tags instancename

List the tags of the given instance.

REMOVE-TAGS

remove-tags [ --from file ] instancename tag ...

Remove tags from the given instance. 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.

REPORTING BUGS

Report bugs to <URL:http://code.google.com/p/ganeti/> or contact the developers using the ganeti mailing list <ganeti@googlegroups.com>.

SEE ALSO

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

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.