HP VPN Firewall Appliances Network Management Command Reference

184
Examples
# Enable address check on the DHCP relay agent.
<Sysname> system-view
[Sysname] interface gigabitethernet 0/1
[Sysname-GigabitEthernet0/1] dhcp relay address-check enable
dhcp relay check mac-address
Use dhcp relay check mac-address to enable MAC address check on the DHCP relay agent.
Use undo dhcp relay check mac-address to disable MAC address check on the DHCP relay agent.
Syntax
dhcp relay check mac-address
undo dhcp relay check mac-address
Default
This function is disabled.
Views
Interface view
Default command level
2: System level
Usage guidelines
With this function enabled, the DHCP relay agent compares the chaddr field of a received DHCP request
with the source MAC address field of the frame. If they are the same, the DHCP relay agent decides this
request as valid and forwards it to the DHCP server; if not, the DHCP request is discarded.
DHCP relay agents change the source MAC addresses when forwarding DHCP packets. Therefore, you
can enable MAC address check only on a DHCP relay agent directly connected to the DHCP clients.
Otherwise, valid DHCP packets might be discarded and clients cannot obtain IP addresses.
Examples
# Enable MAC address check on the DHCP relay agent.
<Sysname> system-view
[Sysname] interface gigabitethernet 0/1
[Sysname-GigabitEthernet0/1] dhcp relay check mac-address
dhcp relay client-detect enable
Use dhcp relay client-detect enable to enable offline detection on the DHCP relay agent.
Use undo dhcp relay client-detect enable to disable offline detection on the DHCP relay agent.
Syntax
dhcp relay client-detect enable
undo dhcp relay client-detect enable
Default
This function is disabled.