libvirt: virtlockd
Description: libvirt, virtualization, virtualization API

# virtlockd

libvirt lock management daemon

Manual section:

  8

Manual group:

  Virtualization Support

## SYNOPSIS

virtlockd [OPTION]...

## DESCRIPTION

The virtlockd program is a server side daemon component of the libvirt virtualization management system that is used to manage locks held against virtual machine resources, such as their disks.

This daemon is not used directly by libvirt client applications, rather it is called on their behalf by libvirtd. By maintaining the locks in a standalone daemon, the main libvirtd daemon can be restarted without risk of losing locks. The virtlockd daemon has the ability to re-exec() itself upon receiving SIGUSR1, to allow live upgrades without downtime.

The virtlockd daemon listens for requests on a local Unix domain socket.

## OPTIONS

-h, --help

Display command line help usage then exit.

-d, --daemon

Run as a daemon and write PID file.

-f, --config FILE

Use this configuration file, overriding the default value.

-t, --timeout SECONDS

Automatically shutdown after SECONDS have elapsed with no active client or lock.

-p, --pid-file FILE

Use this name for the PID file, overriding the default value.

-v, --verbose

Enable output of verbose messages.

-V, --version

Display version information then exit.

## SIGNALS

On receipt of SIGUSR1, virtlockd will re-exec() its binary, while maintaining all current locks and clients. This allows for live upgrades of the virtlockd service.

## FILES

### When run as root

- /etc/libvirt/virtlockd.conf

The default configuration file used by virtlockd, unless overridden on the command line using the -f | --config option.

- /var/run/libvirt/virtlockd-sock

The sockets virtlockd will use.

- /var/run/virtlockd.pid

The PID file to use, unless overridden by the -p | --pid-file option.

### When run as non-root

- $XDG_CONFIG_HOME/libvirt/virtlockd.conf

The default configuration file used by virtlockd, unless overridden on the command line using the -f | --config option.

- $XDG_RUNTIME_DIR/libvirt/virtlockd-sock

The socket virtlockd will use.

- $XDG_RUNTIME_DIR/libvirt/virtlockd.pid

The PID file to use, unless overridden by the -p | --pid-file option.

If $XDG_CONFIG_HOME is not set in your environment, virtlockd will use $HOME/.config

If $XDG_RUNTIME_DIR is not set in your environment, virtlockd will use $HOME/.cache

## EXAMPLES

To retrieve the version of virtlockd:

    # virtlockd --version
    virtlockd (libvirt) 12.2.0

To start virtlockd, instructing it to daemonize and create a PID file:

    # virtlockd -d
    # ls -la /var/run/virtlockd.pid
    -rw-r--r-- 1 root root 6 Jul  9 02:40 /var/run/virtlockd.pid

## BUGS

Please report all bugs you discover. This should be done via either:

1. the mailing list

   https://libvirt.org/contact.html

2. the bug tracker

   https://libvirt.org/bugs.html

Alternatively, you may report bugs to your software distributor / vendor.

## AUTHORS

Please refer to the AUTHORS file distributed with libvirt.

## COPYRIGHT

Copyright (C) 2006-2013 Red Hat, Inc., and the authors listed in the libvirt AUTHORS file.

## LICENSE

virtlockd is distributed under the terms of the GNU LGPL v2.1+. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE

## SEE ALSO

libvirtd(8), https://libvirt.org/