Ubuntu Manpage: firewalld - Dynamic Firewall Manager

NAME

       firewalld - Dynamic Firewall Manager

SYNOPSIS


       firewalld [OPTIONS...]

DESCRIPTION

       firewalld provides a dynamically managed firewall with support for network/firewall zones to define the
       trust level of network connections or interfaces. It has support for IPv4, IPv6 firewall settings and for
       ethernet bridges and has a separation of runtime and permanent configuration options. It also supports an
       interface for services or applications to add firewall rules directly.

OPTIONS

These are the command line options of firewalld:

-h, --help
Prints a short help text and exits.

--default-config
Path to firewalld default configuration. This usually defaults to /usr/lib/firewalld.

--debug[=level]
Set the debug level for firewalld to level. The range of the debug level is 1 (lowest level) to 10
(highest level). The debug output will be written to the firewalld log file specified by --log-file.

--debug-gc
Print garbage collector leak information. The collector runs every 10 seconds and if there are leaks,
it prints information about the leaks.

--log-target
Define the output target to which log messages are written. In mixed mode, Firewalld writes
info-level log messages to syslog. Debug messages are written to a file (see the --log-file
parameter). Info messages also go to stdout and stderr. The syslog, file or console modes write all
messages to the one configured target only.

--log-file
Define the file where debug messages are written to. The default file is /var/log/firewalld.

--nofork
Turn off daemon forking. Force firewalld to run as a foreground process instead of as a daemon in the
background.

--nopid
Disable writing pid file. By default the program will write a pid file. If the program is invoked
with this option it will not check for an existing server process.

--system-config
Path to firewalld system (user) configuration. This usually defaults to /etc/firewalld.

CONCEPTS

firewalld has a D-Bus interface for firewall configuration of services and applications. It also has a
command line client for the user. Services or applications already using D-Bus can request changes to the
firewall with the D-Bus interface directly. For more information on the firewalld D-Bus interface, please
have a look at firewalld.dbus(5).

firewalld provides support for zones, predefined services and ICMP types and has a separation of runtime
and permanent configuration options. Permanent configuration is loaded from XML files in
/usr/lib/firewalld (--default-config) or /etc/firewalld (--system-config) (see the section called
“DIRECTORIES”).

If NetworkManager is not in use and firewalld gets started after the network is already up, the
connections and manually created interfaces are not bound to the zone specified in the ifcfg file. The
interfaces will automatically be handled by the default zone. firewalld will also not get notified about
network device renames. All this also applies to interfaces that are not controlled by NetworkManager if
NM_CONTROLLED=no is set.

You can add these interfaces to a zone with firewall-cmd [--permanent] --zone=zone
--add-interface=interface. If there is a /etc/sysconfig/network-scripts/ifcfg-interface file, firewalld
tries to change the ZONE=zone setting in this file.

If firewalld gets reloaded, it will restore the interface bindings that were in place before reloading to
keep interface bindings stable in the case of NetworkManager uncontrolled interfaces. This mechanism is
not possible in the case of a firewalld service restart.

It is essential to keep the ZONE= setting in the ifcfg file consistent to the binding in firewalld in the
case of NetworkManager uncontrolled interfaces.

Zones
A network or firewall zone defines the trust level of the interface used for a connection. There are
several pre-defined zones provided by firewalld. Zone configuration options and generic information about
zones are described in firewalld.zone(5)

Services
A service can be a list of local ports, protocols and destinations and additionally also a list of
firewall helper modules automatically loaded if a service is enabled. Service configuration options and
generic information about services are described in firewalld.service(5). The use of predefined services
makes it easier for the user to enable and disable access to a service.

ICMP types
The Internet Control Message Protocol (ICMP) is used to exchange information and also error messages in
the Internet Protocol (IP). ICMP types can be used in firewalld to limit the exchange of these messages.
For more information, please have a look at firewalld.icmptype(5).

Runtime configuration
Runtime configuration is the actual active configuration and is not permanent. After reload/restart of
the service or a system reboot, runtime settings will be gone if they haven't been also in permanent
configuration.

Permanent configuration
The permanent configuration is stored in config files and will be loaded and become new runtime
configuration with every machine boot or service reload/restart.

Direct interface
DEPRECATED

The direct interface has been deprecated. It will be removed in a future release. It is superseded by
policies, see firewalld.policies(5).

The direct interface is mainly used by services or applications to add specific firewall rules. It
requires basic knowledge of ip(6)tables concepts (tables, chains, commands, parameters, targets).

DIRECTORIES

       firewalld supports two configuration directories:

   Default/Fallback configuration in /usr/lib/firewalld (--default-config)
       This directory contains the default and fallback configuration provided by firewalld for icmptypes,
       services and zones. The files provided with the firewalld package should not get changed and the changes
       are gone with an update of the firewalld package. Additional icmptypes, services and zones can be
       provided with packages or by creating files.

   System configuration settings in /etc/firewalld (--system-config)
       The system or user configuration stored here is either created by the system administrator or by
       customization with the configuration interface of firewalld or by hand. The files will overload the
       default configuration files.

       To manually change settings of pre-defined icmptypes, zones or services, copy the file from the default
       configuration directory to the corresponding directory in the system configuration directory and change
       it accordingly.

       For more information on icmptypes, please have a look at the firewalld.icmptype(5) man page, for services
       at firewalld.service(5) and for zones at firewalld.zone(5).

SIGNALS

       Currently only SIGHUP is supported.

   SIGHUP
       Reloads the complete firewall configuration. You can also use firewall-cmd --reload. All runtime
       configuration settings will be restored. Permanent configuration will change according to options defined
       in the configuration files.

NOTES

       firewalld home page:
           http://firewalld.org

AUTHORS

       Thomas Woerner <twoerner@redhat.com>
           Developer

       Jiri Popelka <jpopelka@redhat.com>
           Developer

       Eric Garver <eric@garver.life>
           Developer

firewalld 2.3.0                                                                                     FIREWALLD(1)