Configuration procedure ······································································································································ 19

Verifying the configuration ··································································································································· 19

DHCP overview ·························································································································································· 21

DHCP address allocation ·············································································································································· 21

Allocation mechanisms ········································································································································· 21

Dynamic IP address allocation process··············································································································· 22

IP address lease extension···································································································································· 22

DHCP message format ··················································································································································· 23

DHCP options ································································································································································· 24

Common DHCP options ········································································································································ 24

Custom DHCP options ··········································································································································· 24

Protocols and standards ················································································································································ 26

Configuring the DHCP server ···································································································································· 27

Overview ········································································································································································· 27

DHCP address pool ··············································································································································· 27

IP address allocation sequence ···························································································································· 28

DHCP server configuration task list ······························································································································ 29

Configuring an address pool on the DHCP server ····································································································· 29

Configuration task list ··········································································································································· 29

Creating a DHCP address pool ··························································································································· 30

Specifying IP address ranges for a DHCP address pool ·················································································· 30

Configuring gateways for the client ···················································································································· 33

Configuring a domain name suffix for the client ······························································································· 34

Configuring DNS servers for the client ··············································································································· 34

Configuring WINS servers and NetBIOS node type for the client ·································································· 34

Configuring BIMS server information for the client ···························································································· 35

Configuring the TFTP server and boot file name for the client ········································································· 35

Specifying a server for the DHCP client ·············································································································· 36

Configuring Option 184 parameters for the client ···························································································· 36

Configuring self-defined DHCP options ·············································································································· 37

Enabling DHCP ······························································································································································ 38

Enabling the DHCP server on an interface ·················································································································· 38

Applying an address pool on an interface ················································································································· 38

Configuring IP address conflict detection ···················································································································· 39

Enabling handling of Option 82 ·································································································································· 39

Configuring DHCP server compatibility ······················································································································· 40

Configuring the DHCP server to broadcast all responses ················································································· 40

Configure the DHCP server to ignore BOOTP requests ···················································································· 40

Configuring the DHCP server to send BOOTP responses in the format specified in RFC 1048 ·················· 40

Displaying and maintaining the DHCP server ············································································································ 41

DHCP server configuration examples ·························································································································· 41

Static IP address assignment configuration example························································································· 42

Dynamic IP address assignment configuration example ··················································································· 43

DHCP user class configuration example ············································································································· 44

Self-defined option configuration example ········································································································· 46

Troubleshooting DHCP server configuration ··············································································································· 46

Symptom ································································································································································· 46

Analysis ·································································································································································· 47

Solution ··································································································································································· 47

Configuring the DHCP relay agent ··························································································································· 48

Operation ······························································································································································· 48

DHCP relay agent support for Option 82 ·········································································································· 49