podman-machine-init - Initialize a new virtual machine

Description

Initialize a new virtual machine for Podman.

The default machine name is podman-machine-default. If a machine name is not specified as an argument,
then the new machine will be named podman-machine-default.

Rootless only.

Podman on MacOS and Windows requires a virtual machine. This is because containers are Linux - containers
do not run on any other OS because containers' core functionality are tied to the Linux kernel. Podman
machine must be used to manage MacOS and Windows machines, but can be optionally used on Linux.

podmanmachineinit initializes a new Linux virtual machine where containers are run. SSH keys are
automatically generated to access the VM, and system connections to the root account and a user account
inside the VM are added.

By default, the VM distribution is Fedora CoreOS except for WSL which is based on a custom Fedora image.
While Fedora CoreOS upgrades come out every 14 days, the automatic update mechanism Zincata is disabled
by Podman machine.

To check if there is an upgrade available for your machine os, you can run the following command:

$ podman machine ssh 'sudo rpm-ostree upgrade --check'

If an update is available, you can rerun the above command and remove the --check and your operating
system will be updated. After updating, you must stop and start your machine with podmanmachinestop&&podmanmachinestart for it to take effect.

Note: Updating as described above can result in version mismatches between Podman on the host and Podman
in the machine. Executing podmaninfo should reveal versions of both. A configuration where the Podman
host and machine mismatch are unsupported.

For more information on updates and advanced configuration, see the Fedora CoreOS documentation about
auto-updates and update strategies.

Fedora CoreOS upgrades come out every 14 days and are detected and installed automatically. The VM is
rebooted during the upgrade. For more information on updates and advanced configuration, see the Fedora
CoreOS documentation about auto-updates and update strategies.

Default Podman machine settings can be set via the [machine] section in the containers.conf(5) file.

Examples

       Initialize the default Podman machine, pulling the content from the internet.

       $ podman machine init

       Initialize a Podman machine for the specified name pulling the content from the internet.

       $ podman machine init myvm

       Initialize  the  default Podman machine pulling the content from the internet defaulting to rootful mode.
       The default is rootless.

       $ podman machine init --rootful

       Initialize the default Podman machine overriding its disk size override, pulling  the  content  from  the
       internet.

       $ podman machine init --disk-size 50

       Initialize  the  specified  Podman  machine  overriding  its  memory  size,  pulling the content from the
       internet.

       $ podman machine init --memory=1024 myvm

       Initialize the default Podman machine with the host directory /Users mounted into the VM at /Users.

       $ podman machine init -v /Users:/Users

       Initialize the default Podman machine  with  a  usb  device  passthrough  specified  with  options.  Only
       supported for QEMU Machines.

       $ podman machine init --usb vendor=13d3,product=5406

       Initialize  the  default  Podman  machine with a usb device passthrough with specified with options. Only
       supported for QEMU Machines.

       $ podman machine init --usb bus=1,devnum=3

History

       March 2021, Originally compiled by Ashley Cui acui@redhat.com ⟨mailto:acui@redhat.com⟩

                                                                                          podman-machine-init(1)

Name

       podman-machine-init - Initialize a new virtual machine

Options

--cpus=number
Number of CPUs.

--disk-size=number
Size of the disk for the guest VM in GiB.

--help
Print usage statement.

--ignition-path
Fully qualified path of the ignition file.

If an ignition file is provided, the file is copied into the user's CONF_DIR and renamed. Additionally,
no SSH keys are generated, nor are any system connections made. It is assumed that the user does these
things manually or handled otherwise.

--image
Fully qualified registry, path, or URL to a VM image. Registry target must be in the form of
docker://registry/repo/image:version.

Note: Only images provided by podman will be supported.

--memory,-m=number
Memory (in MiB). Note: 1024MiB = 1GiB.

--now
Start the virtual machine immediately after it has been initialized.

--playbook
Add the provided Ansible playbook to the machine and execute it after the first boot.

Note: The playbook will be executed with the same privileges given to the user in the virtual machine.
The playbook provided cannot include other files from the host system, as they will not be copied. Use
of the --playbook flag will require the image to include Ansible. The default image provided will have
Ansible included.

--rootful
Whether this machine prefers rootful (true) or rootless (false) container execution. This option
determines the remote connection default if there is no existing remote connection configurations.

API forwarding, if available, follows this setting.

--timezone
Set the timezone for the machine and containers. Valid values are local or a timezone such as
America/Chicago. A value of local, which is the default, means to use the timezone of the machine host.

The timezone setting is not used with WSL. WSL automatically sets the timezone to the same as the host
Windows operating system.

--usb=bus=number,devnum=numberorvendor=hexadecimal,product=hexadecimal
Assign a USB device from the host to the VM via USB passthrough. Only supported for QEMU Machines.

The device needs to have proper permissions in order to be passed to the machine. This means the device
needs to be under your user group.

Note that using bus and device number are simpler but the values can change every boot or when the device
is unplugged.

When specifying a USB using vendor and product ID's, if more than one device has the same vendor and
product ID, the first available device is assigned.

--user-mode-networking
Indicates that this machine relays traffic from the guest through a user-space process running on the
host. In some VPN configurations the VPN may drop traffic from alternate network interfaces, including VM
network devices. By enabling user-mode networking (a setting of true), VPNs observe all podman machine
traffic as coming from the host, bypassing the problem.

When the qemu backend is used (Linux, Mac), user-mode networking is mandatory and the only allowed value
is true. In contrast, The Windows/WSL backend defaults to false, and follows the standard WSL network
setup. Changing this setting to true on Windows/WSL informs Podman to replace the WSL networking setup
on start of this machine instance with a user-mode networking distribution. Since WSL shares the same
kernel across distributions, all other running distributions reuses this network. Likewise, when the
last machine instance with a true setting stops, the original networking setup is restored.

--username
Username to use for executing commands in remote VM. Default value is core for FCOS and user for Fedora
(default on Windows hosts). Should match the one used inside the resulting VM image.

--volume,-v=source:target[:options]
Mounts a volume from source to target.

Create a mount. If /host-dir:/machine-dir is specified as the *source:target*, Podman mounts host-dir in
the host to machine-dir in the Podman machine.

Additional options may be specified as a comma-separated string. Recognized options are: * ro: mount
volume read-only * rw: mount volume read/write (default) * security_model=[model]: specify 9p security
model (see below)

The 9p security model [determines]
https://wiki.qemu.org/Documentation/9psetup#Starting_the_Guest_directly if and how the 9p filesystem
translates some filesystem operations before actual storage on the host.

In order to allow symlinks to work, on MacOS the default security model is
none.

The value of mapped-xattr specifies that 9p store symlinks and some file attributes as extended
attributes on the host. This is suitable when the host and the guest do not need to interoperate on the
shared filesystem, but has caveats for actual shared access; notably, symlinks on the host are not usable
on the guest and vice versa. If interoperability is required, then choose none instead, but keep in mind
that the guest is not able to do things that the user running the virtual machine cannot do, e.g. create
files owned by another user. Using none is almost certainly the best choice for read-only volumes.

Example: -v"$HOME/git:$HOME/git:ro,security_model=none"

Default volume mounts are defined in containers.conf. Unless changed, the default values is $HOME:$HOME.

NoteonWindowsSubsystemforLinux(WSL) Since all drives are mounted at /mnt on startup by default in
WSL, passing --volume is redundant and has no effect. The host home directory for a C: drive will be
mounted at /mnt/c/Users/<myusername>.