322 Chapter 4: LAN Connections
Figure 4-49 DHCP Pool Status
To display address con?¬‚icts found by a DHCP server when addresses are offered to the
client, use the show ip dhcp con?¬‚ict command in user EXEC or privileged EXEC mode:
sshhooww iipp ddhhccpp ccoonnfflliicctt [ip-address]
The server uses ping to detect con?¬‚icts. The client uses Gratuitous Address Resolution
Protocol (ARP) to detect clients. If an address con?¬‚ict is detected, the address is
removed from the pool and the address is not assigned until an administrator resolves the
con?¬‚ict.
Example 4-17 displays the detection method and detection time for all IP addresses offered
by the DHCP server that have con?¬‚icts with other devices. Table 4-12 outlines the ?¬?eld
descriptions.
Example 4-17 Detection Method and Detection Time
Router# sshhooww iipp ddhhccpp ccoonnfflliicctt
IP address Detection Method Detection time
172.16.1.32 Ping Feb 16 1998 12:28 PM
172.16.1.64 Gratuitous ARP Feb 23 1998 08:12 AM
Table 4-12 show ip dhcp con?¬‚ict Command Field Descriptions
Field Description
IP address The IP address of the host as recorded on the DHCP server
Detection Method The manner in which the IP addresses of the hosts were found on the
DHCP server, which can be a ping or a gratuitous ARP
Detection time The date and time when the con?¬‚ict was found
Accessing Remote Devices 323
Summary Using a Cisco Router as a DHCP Server
The following list summarizes the key points that were discussed in the previous sections:
?– DHCP is built on a client-server model.
Pages:
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459