1# dhcpcd 2 3dhcpcd is a 4[DHCP](http://en.wikipedia.org/wiki/Dynamic_Host_Configuration_Protocol) and a 5[DHCPv6](http://en.wikipedia.org/wiki/DHCPv6) client. 6It's also an IPv4LL (aka [ZeroConf](http://en.wikipedia.org/wiki/Zeroconf)) 7client. 8In layman's terms, dhcpcd runs on your machine and silently configures your 9computer to work on the attached networks without trouble and mostly without 10configuration. 11 12If you're a desktop user then you may also be interested in 13[Network Configurator (dhcpcd-ui)](http://roy.marples.name/projects/dhcpcd-ui) 14which sits in the notification area and monitors the state of the network via 15dhcpcd. 16It also has a nice configuration dialog and the ability to enter a pass phrase 17for wireless networks. 18 19dhcpcd may not be the only daemon running that wants to configure DNS on the 20host, so it uses [openresolv](http://roy.marples.name/projects/openresolv) 21to ensure they can co-exist. 22 23See [BUILDING.md](BUILDING.md) for how to build dhcpcd. 24 25If you wish to file a support ticket or help out with development, please 26[visit the Development Area](https://dev.marples.name/project/profile/101/) 27or join the mailing list below. 28 29## Configuration 30 31You should read the 32[dhcpcd.conf man page](http://roy.marples.name/man/html5/dhcpcd.conf.html) 33and put your options into `/etc/dhcpcd.conf`. 34The default configuration file should work for most people just fine. 35Here it is, in case you lose it. 36 37``` 38# A sample configuration for dhcpcd. 39# See dhcpcd.conf(5) for details. 40 41# Allow users of this group to interact with dhcpcd via the control socket. 42#controlgroup wheel 43 44# Inform the DHCP server of our hostname for DDNS. 45hostname 46 47# Use the hardware address of the interface for the Client ID. 48#clientid 49# or 50# Use the same DUID + IAID as set in DHCPv6 for DHCPv4 ClientID as per RFC4361. 51# Some non-RFC compliant DHCP servers do not reply with this set. 52# In this case, comment out duid and enable clientid above. 53duid 54 55# Persist interface configuration when dhcpcd exits. 56persistent 57 58# Rapid commit support. 59# Safe to enable by default because it requires the equivalent option set 60# on the server to actually work. 61option rapid_commit 62 63# A list of options to request from the DHCP server. 64option domain_name_servers, domain_name, domain_search, host_name 65option classless_static_routes 66# Respect the network MTU. This is applied to DHCP routes. 67option interface_mtu 68 69# Most distributions have NTP support. 70#option ntp_servers 71 72# A ServerID is required by RFC2131. 73require dhcp_server_identifier 74 75# Generate SLAAC address using the Hardware Address of the interface 76#slaac hwaddr 77# OR generate Stable Private IPv6 Addresses based from the DUID 78slaac private 79``` 80 81The [dhcpcd man page](/man/html8/dhcpcd.html) has a lot of the same options and more, which only apply to calling dhcpcd from the command line. 82 83 84## Compatibility 85dhcpcd-5 is only fully command line compatible with dhcpcd-4 86For compatibility with older versions, use dhcpcd-4 87 88## Upgrading 89dhcpcd-7 defaults the database directory to `/var/db/dhcpcd` instead of 90`/var/db` and now stores dhcpcd.duid and dhcpcd.secret in there instead of 91in /etc. 92 93dhcpcd-9 defaults the run directory to `/var/run/dhcpcd` instead of 94`/var/run` and the prefix of dhcpcd has been removed from the files. 95 96## ChangeLog 97We no longer supply a ChangeLog. 98However, you're more than welcome to read the 99[commit log](http://roy.marples.name/git/dhcpcd.git/log/) and 100[archived release announcements](http://roy.marples.name/archives/dhcpcd-discuss/). 101