506 IP Addressing Commands
User Guidelines
This command only applies to routing interfaces. When DHCP is enabled on
a routing interface, the system automatically deletes all manually configured
IPv4 addresses on the interface.
• The command
no ip address dhcp
removes the interface’s primary address
(Manual/DHCP) including the secondary addresses, if configured, and sets
the Interface method to
None
.
• The command
no ip address
removes the interface’s primary address only
if configured through DHCP and sets the interface method to
None
. It
does not remove a manually configured address.
In addition to leasing an IP address and subnet mask, the DHCP client may
learn the following parameters from a DHCP server:
• The IPv4 address of a default gateway. If the device learns different default
gateways on different interfaces, the system uses the first default gateway
learned. The system installs a default route in the routing table, with the
default gateway’s address as the next hop address. This default route has a
preference of 254.
• The IPv4 address of a DNS server. The DNS client stores each DNS server
address in its server list.
• A domain name. The DNS client stores each domain name in its domain
name list.
Examples
To enable DHCPv4 on vlan 2:
console#config
console(config)#interface vlan 2
console(config-if-vlan2)#ip address dhcp
ip default-gateway
Use the ip default-gateway command in Global Configuration mode to
configure a default gateway (router).
2CSPC4.XCT-SWUM2XX1.book Page 506 Monday, October 3, 2011 11:05 AM