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.