Dhcp Snooping Check Request-Message - HP 6125XLG Command Reference Manual

Usage guidelines
With MAC address check enabled, DHCP snooping compares the chaddr field of a received DHCP
request with the source MAC address field in the frame header. If they are the same, DHCP snooping
considers this request valid and forwards it to the DHCP server. If they are not the same, DHCP snooping
discards the DHCP request.
Examples
# Enable MAC address check for DHCP snooping.
<Sysname> system-view
[Sysname] interface Ten-GigabitEthernet 1/1/5
[Sysname-Ten-GigabitEthernet1/1/5] dhcp snooping check mac-address

dhcp snooping check request-message

Use dhcp snooping check request-message to enable DHCP-REQUEST check for DHCP snooping.
Use undo dhcp snooping check request-message to disable DHCP-REQUEST check for DHCP snooping.
Syntax
dhcp snooping check request-message
undo dhcp snooping check request-message
Default
This function is disabled.
Views
Ethernet interface view, aggregate interface view
Predefined user roles
network-admin
Usage guidelines
DHCP-REQUEST packets include lease renewal packets, DHCP-DECLINE packets, and DHCP-RELEASE
packets. This function prevents unauthorized clients that forge DHCP-REQUEST packets from attacking the
DHCP server.
With this function enabled, DHCP snooping looks for a matching DHCP snooping entry for each
received DHCP-REQUEST message.
If a match is found, DHCP snooping compares the entry with the message. If they have consistent
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information, DHCP snooping considers the packet valid and forwards it to the DHCP server. If they
have different information, DHCP snooping considers the message invalid and discards it.
If no match is found, DHCP snooping forwards the message to the DHCP server.
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Examples
# Enable DHCP-REQUEST check for DHCP snooping.
<Sysname> system-view
[Sysname] interface Ten-GigabitEthernet 1/1/5
[Sysname-Ten-GigabitEthernet1/1/5] dhcp snooping check request-message
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