iii 
Enabling the DHCP server on an interface ······································································································ 53 
Applying an address pool on an interface ········································································································ 53 
Configuring a DHCP policy for dynamic address assignment ········································································· 53 
Configuring IP address conflict detection ········································································································· 54 
Enabling handling of Option 82 ························································································································ 55 
Configuring DHCP server compatibility ············································································································ 55 
Configuring the DHCP server to broadcast all responses ········································································ 55 
Configure the DHCP server to ignore BOOTP requests ·········································································· 56 
Configuring the DHCP server to send BOOTP responses in RFC 1048 format ······································ 56 
Setting the DSCP value for DHCP packets sent by the DHCP server ····························································· 56 
Configuring DHCP binding auto backup ·········································································································· 57 
Configuring address pool usage alarming ······································································································· 57 
Binding gateways to a common MAC address ································································································ 58 
Advertising subnets assigned to clients ··········································································································· 58 
Applying a DHCP address pool to a VPN instance ·························································································· 59 
Enabling client offline detection on the DHCP server ······················································································ 60 
Enabling DHCP logging on the DHCP server ·································································································· 60 
Displaying and maintaining the DHCP server ·································································································· 61 
DHCP server configuration examples ·············································································································· 61 
Static IP address assignment configuration example ·············································································· 61 
Dynamic IP address assignment configuration example ········································································· 63 
DHCP user class configuration example ·································································································· 65 
DHCP user class whitelist configuration example ···················································································· 66 
Primary and secondary subnets configuration example ·········································································· 67 
DHCP option customization configuration example ················································································· 69 
Troubleshooting DHCP server configuration ··································································································· 70 
Symptom ·················································································································································· 70 
Analysis ···················································································································································· 70 
Solution ···················································································································································· 70 
Configuring the DHCP relay agent ································································ 72 
Overview ·························································································································································· 72 
Operation ················································································································································· 72 
DHCP relay agent support for Option 82 ································································································· 73 
DHCP relay agent configuration task list ········································································································· 73 
Enabling DHCP ················································································································································ 74 
Enabling the DHCP relay agent on an interface ······························································································ 74 
Specifying DHCP servers on a relay agent ······································································································ 74 
Specifying the source address and gateway address in DHCP requests ························································ 75 
Configuring the DHCP relay agent security features ······················································································· 75 
Enabling the DHCP relay agent to record relay entries ··········································································· 75 
Enabling periodic refresh of dynamic relay entries ·················································································· 76 
Enabling DHCP starvation attack protection ···························································································· 76 
Configuring the DHCP relay agent to release an IP address ··········································································· 77 
Configuring Option 82 ······································································································································ 78 
Setting the DSCP value for DHCP packets sent by the DHCP relay agent ····················································· 78 
Enabling DHCP server proxy on a DHCP relay agent ····················································································· 79 
Configuring a DHCP relay address pool ·········································································································· 79 
Specifying a gateway address for DHCP clients ······························································································ 80 
Enabling client offline detection on the DHCP relay agent ·············································································· 80 
Configuring the DHCP smart relay feature ······································································································ 81 
Displaying and maintaining the DHCP relay agent ·························································································· 82 
DHCP relay agent configuration examples ······································································································ 83 
DHCP relay agent configuration example ································································································ 83 
Option 82 configuration example ············································································································· 84 
Troubleshooting DHCP relay agent configuration ···························································································· 84 
Symptom ·················································································································································· 84 
Analysis ···················································································································································· 84 
Solution ···················································································································································· 84 
Configuring the DHCP client ········································································· 86 
Enabling the DHCP client on an interface ········································································································ 86