The multipass launch command without any argument will create and start a new instance based on the default image, using a random generated name:
$ multipass launch
…
Launched: relishing-lionfish
You can then shell into that instance by its name:
$ multipass shell relishing-lionfish
…
multipass@relishing-lionfish:~$
The full multipass help launch output explains the available options:
$ multipass help launch
Usage: multipass launch [options] [[<remote:>]<image> | <url>]
Create and start a new instance.
Options:
-h, --help Displays help on commandline options.
--help-all Displays help including Qt specific
options.
-v, --verbose Increase logging verbosity. Repeat the
'v' in the short option for more detail.
Maximum verbosity is obtained with 4 (or
more) v's, i.e. -vvvv.
-c, --cpus <cpus> Number of CPUs to allocate.
Minimum: 1, default: 1.
-d, --disk <disk> Disk space to allocate. Positive
integers, in bytes, or with K, M, G
suffix.
Minimum: 512M, default: 5G.
-m, --memory <memory> Amount of memory to allocate. Positive
integers, in bytes, or decimals, with K,
M, G suffix.
Minimum: 128M, default: 1G.
-n, --name <name> Name for the instance. If it is
'primary' (the configured primary
instance name), the user's home
directory is mounted inside the newly
launched instance, in 'Home'.
--cloud-init <file> | <url> Path or URL to a user-data cloud-init
configuration, or '-' for stdin
--network <spec> Add a network interface to the
instance, where <spec> is in the
"key=value,key=value" format, with the
following keys available:
name: the network to connect to
(required), use the networks command for
a list of possible values, or use
'bridged' to use the interface
configured via `multipass set
local.bridged-network`.
mode: auto|manual (default: auto)
mac: hardware address (default:
random).
You can also use a shortcut of "<name>"
to mean "name=<name>".
--bridged Adds one `--network bridged` network.
--mount <local-path>:<instance-path> Mount a local directory inside the
instance. If <instance-path> is omitted,
the mount point will be the same as the
absolute path of <local-path>
--timeout <timeout> Maximum time, in seconds, to wait for
the command to complete. Note that some
background operations may continue
beyond that. By default, instance
startup and initialization is limited to
5 minutes each.
Arguments:
image Optional image to launch. If omitted,
then the default Ubuntu LTS will be
used.
<remote> can be either ‘release’ or
‘daily‘. If <remote> is omitted,
‘release’ will be used.
<image> can be a partial image hash or
an Ubuntu release version, codename or
alias.
<url> is a custom image URL that is in
http://, https://, or file:// format.
The only, optional, positional argument is the image to launch an instance from. See the multipass find documentation for information on what images are available. It’s also possible to provide a full URL to the image (use file:// for an image available on the host running multipassd).
You can change the resources made available to the instance by passing any of --cpu, --disk, --memory options, allowing for more CPU cores, disk space or RAM, respectively.
If you want your instance to have a name of your choice, use --name. It has to be unique, two instances can’t share the same name.
By passing a filename or an URL to --cloud-init, you can provide “user data” to cloud-init to customize the instance on first boot. See their documentation for examples.
The --network option allows launching instances with additional network interfaces. [since version 1.6.0]
Passing --bridged and --network bridged are shortcuts to --network <name>, where <name> is configured via multipass set local.bridged-interface. [since version 1.7.0]
The --mount option allows mounting several folders in the instance by calling the mount command after the instances is launched. It can be specified multiple times, with different mount paths. [since version 1.10.0]
Use --timeout if you need to change how long Multipass waits for the machine to boot and initialize. [since version 1.7.0]