Understanding DHCP Client Operation on ACX Series

 

A Dynamic Host Configuration Protocol (DHCP) client can obtain its TCP/IP settings and the IP address from a DHCP local server. The DHCP server provides the configuration parameters to requesting DHCP clients in the form of an address-lease offer.

For a router to operate as a DHCP client, you configure a logical interface on the router to obtain an IP address from the DHCP server in the network. You can configure the vendor class ID, lease time, DHCP server address, retransmission attempts, and retry interval configuration attributes. You can also renew DHCP client releases.

An ACX Series router acting as a DHCP client obtains IP address and other configuration parameters from a DHCP local server. Upon receiving an IP address from the DHCP server, the DHCP client automatically adds an access internal default route. Unless specific server is configured in client configuration, DHCP client accepts the PDUs from the first DHCP server response.

In a routing instance, if there multiple interfaces acting as DHCP client, default route and domain name server configured in the system will be the one created by last DHCP client.

DHCP client options and address pools are configured in a centralized address pool server. For DHCP clients connected though Ethernet interfaces, the DHCP server automatically adds an access internal host route once the DHCP client obtains an address, specifying the interface as the outbound interface. The route is automatically removed once the DHCP client lease time expires or when the DHCP client releases the address.

Typically, a DHCP server uses the client and option 82 information from DHCP PDUs to assign IP addresses and send other client configuration information.