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{{Article summary start}}
{{Article summary text|A guide to configuring the network using netcfg and network profile scripts.}}
{{Article summary heading|Overview}}
{{Article summary text|{{Networking overview}}}}
{{Article summary heading|Resources}}
{{Article summary wiki|Netcfg Tips}}
{{Article summary wiki|Netcfg Troubleshooting}}
{{Article summary link|Netcfg network scripts repository|https://projects.archlinux.org/netcfg.git/}}
{{Article summary end}}

{{Note|Netcfg has been superseded by [[netctl]].}}

Netcfg is used to configure and manage network connections via profiles. It has pluggable support for a range of connection types, such as wireless, Ethernet and [[Wikipedia:Point-to-point_protocol|PPP]]. It is also capable of starting/stopping many-to-one connections, that is, multiple connections within the same profile, optionally with bonding. Further it is useful for users seeking a simple and robust means of managing multiple network configurations (e.g. laptop users).

== Preparation ==

In the simplest cases, users must at least know the name of their network interface(s) (e.g. {{ic|eth0}}, {{ic|wlan0}}). If configuring a static IP address, the IP addresses of the default gateway and name server(s) must also be known.

If connecting to a wireless network, have some basic information ready. For a wireless network this includes what type of security is used, the network name (ESSID), and any passphrase or encryption keys. Additionally, ensure the proper drivers and firmware are installed for the wireless device, as described in [[Wireless Setup]].

== Installation ==

The {{Pkg|netcfg}} package is available in the [[Official Repositories|official repositories]]. As of {{Pkg|netcfg}} version 2.5.x, optional dependencies include {{Pkg|wpa_actiond}}, which is required for automatic/roaming wireless connections, and {{Pkg|ifplugd}}, which is required for automatic Ethernet configuration. See [https://www.archlinux.org/news/487/ the announcement].

Users wanting [[Bash]] completion support for netcfg, install the {{Pkg|bash-completion}} package from the official repositories.

== Configuration ==
{{Note|1={{Pkg|netcfg}} >= 2.8.9 drops deprecated {{ic|/etc/[[rc.conf]]}} compatibility. Netcfg users should configure all interfaces in {{ic|/etc/conf.d/netcfg}} instead of {{ic|/etc/rc.conf}}.}}

Network profiles are stored in {{ic|/etc/network.d/}}. To minimize the potential for errors, copy an example configuration from {{ic|/etc/network.d/examples/}} to {{ic|/etc/network.d/mynetwork}}. The file name is the name of the network profile, and {{ic|mynetwork}} is used as an example throughout this article.

Depending on the connection type and security, use one of the following examples from {{ic|/etc/network.d/examples/}} as a base.

{{Warning|Be wary of examples found on the internet as they often contain deprecated options that may cause problems!}}

{| class="wikitable" align="center"
! Connection !! Type !! Example Profile !! Information
|-
| rowspan="3"| '''Wired'''
| Dynamic IP || {{ic|ethernet-dhcp}} ||
|-
| Static IP || {{ic|ethernet-static}} ||
|-
| Routed || {{ic|ethernet-iproute}} || Can be checked with {{ic|ip route}} from the {{Pkg|iproute2}} package.
|-
| rowspan="3"| '''Wireless'''
| WPA-Personal
| {{ic|wireless-wpa}} || Uses a passphrase/pre-shared key.
|-
| rowspan="2"| WPA-Enterprise
| {{ic|wireless-wpa-config}} || The {{Pkg|wpa_supplicant}} configuration is external.
|-
| {{ic|wireless-wpa-configsection}} || The {{Pkg|wpa_supplicant}} configuration is stored as a string.
|}

Modify the new configuration file, {{ic|/etc/network.d/mynetwork}}:

* Set {{ic|INTERFACE}} to the correct wireless or Ethernet interface. This can be checked with {{ic|ip link}} and {{ic|iwconfig}}.
* Ensure the {{ic|ESSID}} and {{ic|KEY}} (passphrase) are set correctly for wireless connections. Typos in these fields are common errors.
** Note that WEP ''string'' keys (not ''hex'' keys) must be specified with a leading {{ic|s:}} (e.g. {{ic|1=KEY="s:''somepasskey''"}}).

{{Note|If you are using netcfg inside a VPS, please see [[Virtual_Private_Server#Moving_your_VPS_from_network_configuration_in_rc.conf_to_netcfg_.28tested_with_OpenVZ.29|the appropriate page]].}}

{{Note|Netcfg configurations are valid Bash scripts. Any configuration involving special characters such as {{ic|$}} or {{ic|\}} needs to be quoted correctly otherwise it will be interpreted by Bash. To avoid interpretation, use single quotes or backslash escape characters where appropriate.}}

{{Note|Network information (e.g. wireless passkey) will be stored in plain text format, so users may want to change the permissions on the newly created profile (e.g. {{ic|chmod 0600 /etc/network.d/mynetwork}}) to make it readable by root only.}}

{{Note|For WPA-Personal, it is also possible to [[Wpa_supplicant#Classic_method:_.2Fetc.2Fwpa_supplicant.conf|encode the WPA passkey into a hexadecimal string]]. Save the new hexadecimal string into the wireless WPA profile in {{ic|/etc/network.d/mynetwork}} as the value of the {{ic|KEY}} variable (make sure this will be the only {{ic|KEY}} variable enabled), to look similar to this: {{ic|1=KEY='7b271c9a7c8a6ac07d12403a1f0792d7d92b5957ff8dfd56481ced43ec6a6515'}}. However, this key can also be used by anyone to get on your network, and thus must be protected just as well as the cleartext key. The hexadecimal encoding is more convenient if you use special characters that are hard to express in scripts.}}

{{
Note|1=By default netcfg uses dhcpcd for configuring network interfaces. An alternate to dhcpcd is dhclient. To use dhclient, set DHCLIENT='yes' in appropriate profile configuration.
}}

== Manual Operation ==

To connect a profile:

 # netcfg mynetwork

To disconnect a profile:

 # netcfg down mynetwork

If successful, users can configure netcfg to connect automatically or during boot. If the connection fails, see [[Netcfg Troubleshooting]] for solutions and for how to ask for help.

It is also possible to use an interactive menu ({{Pkg|dialog}} package is required):
 netcfg-menu

Additionally, see:

 $ netcfg help

== Automatic Operation ==

=== Just one profile ===

In the simplest case, only one profile will be used and is always desired to start on boot:

 # [[Systemd#Basic_systemctl_usage|systemctl]] enable netcfg@myprofile

=== Net-Profiles ===

Edit the {{ic|NETWORKS}} array in {{ic|/etc/conf.d/netcfg}} to refer to the network config file {{ic|/etc/network.d/mynetwork}}.

{{hc|/etc/conf.d/netcfg|2=
NETWORKS=(mynetwork yournetwork)}}

Start the service on startup:

 # systemctl enable netcfg

Alternatively, the profiles that were active at last shutdown can be restored by setting the {{ic|NETWORKS}} array to {{ic|last}}.

{{hc|/etc/conf.d/netcfg|2=
NETWORKS=(last)}}

{{Note|For {{ic|1=NETWORKS=(last)}} to work, you will have to connect to your network manually first and then stop the daemon for Netcfg to remember the network. You can stop the Netcfg daemon by running {{ic|netcfg-daemon stop}} as root.}}

{{Note|The {{ic|1=NETWORKS=(menu)}} setting cannot be used anymore when switching to systemd. See {{bug|31377}} for details.}}

=== Net-Auto-Wireless ===

This allows users to automatically connect to wireless networks with proper roaming support. To use this feature, the {{Pkg|wpa_actiond}} package is required. Note that {{ic|wireless-wpa-config}} profiles do not work with {{ic|net-auto-wireless}}. Convert them to {{ic|wireless-wpa-configsection}} or {{ic|wireless-wpa}} instead.

Specify the desired wireless interface with the {{ic|WIRELESS_INTERFACE}} variable in {{ic|/etc/conf.d/netcfg}} or define a list of wireless networks that should be automatically connected with the {{ic|AUTO_PROFILES}} variable in {{ic|/etc/conf.d/netcfg}}.

{{Note|If AUTO_PROFILES is not set, all wireless networks will be tried.}}
{{Note|1=By default, wpa_actiond sets dhcp timeout to 10 seconds (line 16 of /usr/bin/netcfg-wpa_actiond-action) which may be not enough for all users to always get an IP address successfully. To override this, for example  with classic 30 seconds timeout, write DHCP_TIMEOUT=30 to /etc/conf.d/netcfg}}
Enable {{ic|net-auto-wireless}} so systemd manages it.

 # systemctl enable net-auto-wireless

=== Net-Auto-Wired ===

This allows users to automatically connect to wired networks. To use this feature, the {{Pkg|ifplugd}} package is required.

Specify the desired wired interface with the {{ic|WIRED_INTERFACE}} variable in {{ic|/etc/conf.d/netcfg}}.

Enable {{ic|net-auto-wired}} so systemd manages it.

 # systemctl enable net-auto-wired

The daemon starts an {{ic|ifplugd}} process which runs {{ic|/etc/ifplugd/netcfg.action}} when the status of the wired interface changes (e.g. a cable is plugged in or unplugged). On plugging in a cable, attempts are made to start any profiles with {{ic|1=CONNECTION = "ethernet"}} or {{ic|"ethernet-iproute"}} and {{ic|1=INTERFACE = WIRED_INTERFACE}} until one of them succeeds.

{{Note|DHCP profiles are tried before static ones, which could lead to undesired results in some cases. However, one can tell netcfg to prefer a particular interface by adding {{ic|1=AUTO_WIRED=1}} to the desired profile.}}

{{Note|The {{ic|net-auto-wired}} daemon cannot start multiple ifplugd processes for multiple interfaces (unlike ifplugd's own {{ic|/etc/rc.d/ifplugd}} which can).}}

== FAQ ==

{{FAQ
|question=Why doesn't netcfg do ''(some feature)''?
|answer=Netcfg does not need to; it connects to networks. Netcfg is modular and re-usable. See {{ic|/usr/lib/network}} for re-usable functions for custom scripts.}}

{{FAQ
|question=Why doesn't netcfg behave in ''this'' way?
|answer=Netcfg does not enforce any rules; it connects to networks. Netcfg does not impose any heuristics, like "disconnect from wireless if Ethernet is connected". If you want such behavior, it should be simple to write a separate tool on top of netcfg. See the question above. Alternatively, you could be creative with the use of netcfg's {{ic|POST_UP}} functionality to handle some use cases.}}

{{FAQ
|question=Do I need anything else if I'm using netcfg?
|answer=This question usually references {{ic|/etc/hostname}}, which still has to be set.}}