QEMU Guest Agent

Synopsis

qemu-ga [OPTIONS]

Description

The QEMU Guest Agent is a daemon intended to be run within virtual machines. It allows the hypervisor host to perform various operations in the guest, such as:

  • get information from the guest

  • set the guest’s system time

  • read/write a file

  • sync and freeze the filesystems

  • suspend the guest

  • reconfigure guest local processors

  • set user’s password

qemu-ga will read a system configuration file on startup (located at /etc/qemu/qemu-ga.conf by default), then parse remaining configuration options on the command line. For the same key, the last option wins, but the lists accumulate (see below for configuration file format).

If an allowed RPCs list is defined in the configuration, then all RPCs will be blocked by default, except for the allowed list.

If a blocked RPCs list is defined in the configuration, then all RPCs will be allowed by default, except for the blocked list.

If both allowed and blocked RPCs lists are defined in the configuration, then all RPCs will be blocked by default, then the allowed list will be applied, followed by the blocked list.

While filesystems are frozen, all except for a designated safe set of RPCs will blocked, regardless of what the general configuration declares.

Options

-c, --config=PATH

Configuration file path (the default is /etc/qemu/qemu-ga.conf, unless overridden by the QGA_CONF environment variable)

-m, --method=METHOD

Transport method: one of unix-listen, virtio-serial, or isa-serial, or vsock-listen (virtio-serial is the default).

-p, --path=PATH

Device/socket path (the default for virtio-serial is /dev/virtio-ports/org.qemu.guest_agent.0, the default for isa-serial is /dev/ttyS0). Socket addresses for vsock-listen are written as <cid>:<port>.

-l, --logfile=PATH

Set log file path (default is stderr).

-f, --pidfile=PATH

Specify pid file (default is /var/run/qemu-ga.pid).

-F, --fsfreeze-hook=PATH

Enable fsfreeze hook. Accepts an optional argument that specifies script to run on freeze/thaw. Script will be called with ‘freeze’/’thaw’ arguments accordingly (default is /etc/qemu/fsfreeze-hook). If using -F with an argument, do not follow -F with a space (for example: -F/var/run/fsfreezehook.sh).

-t, --statedir=PATH

Specify the directory to store state information (absolute paths only, default is /var/run).

-v, --verbose

Log extra debugging information.

-V, --version

Print version information and exit.

-d, --daemon

Daemonize after startup (detach from terminal).

-b, --block-rpcs=LIST

Comma-separated list of RPCs to disable (no spaces, use --block-rpcs=help to list available RPCs).

-a, --allow-rpcs=LIST

Comma-separated list of RPCs to enable (no spaces, use --allow-rpcs=help to list available RPCs).

-D, --dump-conf

Dump the configuration in a format compatible with qemu-ga.conf and exit.

-h, --help

Display this help and exit.

Files

The syntax of the qemu-ga.conf configuration file follows the Desktop Entry Specification, here is a quick summary: it consists of groups of key-value pairs, interspersed with comments.

# qemu-ga configuration sample
[general]
daemonize = 0
pidfile = /var/run/qemu-ga.pid
verbose = 0
method = virtio-serial
path = /dev/virtio-ports/org.qemu.guest_agent.0
statedir = /var/run

The list of keys follows the command line options:

Key

Key type

daemon

boolean

method

string

path

string

logfile

string

pidfile

string

fsfreeze-hook

string

statedir

string

verbose

boolean

block-rpcs

string list

allow-rpcs

string list

See also

qemu(1)