dhcpcd setup

dhcpcd is the demon responsible for querying a DHCP server (i.e., ISC kea) and configure the machine for the network it is about to join from the lease it receives from the DHCP server. A DHCP lease contains

• the IP address for a device.
• the subnet mask.
• the default gateway.
• the IP addresses of DNS servers in the network.
• a unique client identifier (i.e., a hostname).
• the lease duration – the time duration during which the lease is valid. After the lease is expired, dhcpcd automatically request a new lease.

dhcpcd should not be confused with dhcpd – the latter ist the ISC dhcpd, which reached its EOL in the end of 2022.

starting dhcpcd

start dhcpcd for a specific interface, request a lease for the interface, wait for an address to be assigned before forking to background:

start dhcpcd for a specific interface, immediately fork to background, request no lease for the interface:

start dhcpcd for a specific interface, immediately fork to background, request a lease for the interface with a timeout of 10 seconds, write log to file specified in arg <logfile>:

renew lease for a specific interface: