NAME

qemu-ga - 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

AUTHOR

Michael Roth <mdroth@linux.vnet.ibm.com>

COPYRIGHT

2025, The QEMU Project Developers