Service Manual

INTERFACE mode
ip address dhcp
Dynamically assigned IP addresses can be released without removing the DHCP client operation on the interface on a switch
congured as a DHCP client.
3. Manually acquire a new IP address from the DHCP server by releasing a dynamically acquired IP address while retaining the
DHCP client conguration on the interface.
EXEC Privilege mode
release dhcp interface type slot/port[/subport]
4. Acquire a new IP address with renewed lease time from a DHCP server.
EXEC Privilege mode
renew dhcp interface type slot/port[/subport]
To display DHCP client information, use the following show commands in EXEC Privilege mode.
• To display statistics about DHCP client interfaces, use the show ip dhcp client statistics interface type
slot/port[subport] command.
• To clear DHCP client statistics on a specied or on all interfaces, use the clear ip dhcp client statistics {all |
interface type slot/port[/subport]} command.
• To display dynamic IP address lease information currently assigned to a DHCP client interface, use the show ip dhcp lease
[interface
type slot/port[/subport]] command.
• To display log messages for all DHCP packets sent and received on DHCP client interfaces, use the debug ip dhcp client
packets [interface
type slot/port[/subport] command.
• To display log message on DHCP client interfaces for IP address acquisition, IP address release, IP address and lease time
renewal, and release an IP address, use the [no] debug ip dhcp client events [interface type slot/
port
[/subport]] command.
DHCP Client on a Management Interface
These conditions apply when you enable a management interface to operate as a DHCP client.
• The management default route is added with the gateway as the router IP address received in the DHCP ACK packet. It is
required to send and receive trac to and from other subnets on the external network. The route is added irrespective when the
DHCP client and server are in the same or dierent subnets. The management default route is deleted if the management IP
address is released like other DHCP client management routes.
• ip route for 0.0.0.0 takes precedence if it is present or added later.
• Management routes added by a DHCP client display with Route Source as DHCP in the show ip management route and
show ip management-route dynamic command output.
• Management routes added by DHCP are automatically reinstalled if you congure a static IP route with the ip route
command that replaces a management route added by the DHCP client. If you remove the statically congured IP route using
the no ip route command, the management route is reinstalled. Manually delete management routes added by the DHCP
client.
• To reinstall management routes added by the DHCP client that is removed or replaced by the same statically congured
management routes, release the DHCP IP address and renew it on the management interface.
• Management routes added by the DHCP client have higher precedence over the same statically congured management route.
Static routes are not removed from the running conguration if a dynamically acquired management route added by the DHCP
client overwrites a static management route.
• Management routes added by the DHCP client are not added to the running conguration.
NOTE: Management routes added by the DHCP client include the specic routes to reach a DHCP server in a dierent
subnet and the management route.
Dynamic Host Conguration Protocol (DHCP)
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