View and renew a DHCP lease

Reviewer: name contact BSD flavour

Reviewer: Yannick Cadin yannick@diablotin.fr FreeBSD/OpenBSD

Concept

An admin should have a basic understanding of DHCP leases and how to configure a client to override the settings received from a DHCP server. In addition, be able to view the current lease(((lease, DHCP))), release it and renew a lease. Since the DHCP(((DHCP))) client used varies, be familiar with using the DCHP client commands on each BSD.

Introduction

dhclient: Dynamic Host Configuration Protocol (DHCP) client

dhclient.leases: DHCP client lease database

dhclient.conf: DHCP client configuration file

dhcp-options(5): DHCP configuration options

files:

/etc/dhclient.conf

/sbin/dhclient

/sbin/dhclient-script

/var/db/dhclient.leases

configure a client to override the settings received from a DHCP server: use require or supersede options in dhclient.conf

view the current lease (all BSDs):

""less /var/db/dhclient.leases.if_name

release the current lease:

""dhclient -r

request a new lease / renew a lease:

""dhclient ifname

Examples

Practice Exercises

More information

dhclient(8), dhclient.leases(5), dhclient.conf(5), rc.conf(5)

TODO: netbsd also has dhcpcd