HP 6125G Configuration Manual page 5

Configuring DHCP snooping ····································································································································· 48
DHCP snooping functions ·············································································································································· 48
Ensuring that DHCP clients obtain IP addresses from authorized DHCP servers ············································ 48
Recording IP-to-MAC mappings of DHCP clients ······························································································· 48
Application environment of trusted ports ····················································································································· 49
Configuring a trusted port connected to a DHCP server ··················································································· 49
Configuring trusted ports in a cascaded network ······································································································ 49
DHCP snooping support for Option 82 ······················································································································· 50
DHCP snooping configuration task list ························································································································ 51
Configuring DHCP snooping basic functions ·············································································································· 52
Configuring DHCP snooping to support Option 82 ··································································································· 52
Configuring DHCP snooping entries backup ·············································································································· 54
Enabling DHCP starvation attack protection ··············································································································· 55
Enabling DHCP-REQUEST message attack protection ······························································································· 56
Displaying and maintaining DHCP snooping ············································································································· 56
DHCP snooping configuration examples ····················································································································· 57
DHCP snooping configuration example ············································································································· 57
DHCP snooping Option 82 support configuration example ············································································ 57
Configuring BOOTP client ········································································································································· 59
Overview ········································································································································································· 59
BOOTP application ··············································································································································· 59
Obtaining an IP address dynamically ················································································································· 59
Protocols and standards ······································································································································· 59
Configuration restrictions ·············································································································································· 59
Configuring an interface to dynamically obtain an IP address through BOOTP ···················································· 60
Displaying and maintaining BOOTP client configuration ·························································································· 60
BOOTP client configuration example ·························································································································· 60
Network requirements ··········································································································································· 60
Configuration procedure ······································································································································ 60
Configuring IPv4 DNS ··············································································································································· 61
Overview ········································································································································································· 61
Static domain name resolution ····························································································································· 61
Dynamic domain name resolution ······················································································································· 61
Configuring the IPv4 DNS client ·································································································································· 62
Configuring static domain name resolution ········································································································ 62
Configuring dynamic domain name resolution ·································································································· 63
Setting the DSCP value for DNS packets ····················································································································· 63
Specifying the source interface for DNS packets ······································································································· 64
Displaying and maintaining IPv4 DNS ························································································································ 64
Static domain name resolution configuration example ······························································································ 65
Network requirements ··········································································································································· 65
Configuration procedure ······································································································································ 65
Dynamic domain name resolution configuration example ························································································ 66
Network requirements ··········································································································································· 66
Configuration procedure ······································································································································ 66
Verifying the configuration ··································································································································· 68
Troubleshooting IPv4 DNS configuration ···················································································································· 69
Symptom ································································································································································· 69
Solution ··································································································································································· 69
Configuring IP performance optimization ················································································································ 70
Enabling receiving and forwarding of directed broadcasts to a directly connected network ······························· 70
Enabling receiving of directed broadcasts to a directly connected network ·················································· 70
Enabling forwarding of directed broadcasts to a directly connected network ··············································· 70
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