3com S7906E Manuel De Montage

 

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security command to view bindings of DHCP relay agents, and use the display dhcp relay statistics 

command to view statistics of DHCP packets forwarded by DHCP relay agents. 

 

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Performing the configuration on the DHCP server is also required to guarantee the client-server 

communication via the relay agent. Refer to 

 for DHCP 

server configuration information. 

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Because the DHCP relay agent and server are on different subnets, you need to configure a static 

route or dynamic routing protocol to make them reachable to each other. 

 

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As shown in 

, Enable Option 82 on the DHCP relay agent (Switch A). 

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Configure the handling strategy for DHCP requests containing Option 82 as replace. 

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Configure the padding content for the circuit ID sub-option as company001 and for the remote ID 

sub-option as device001. 

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Switch A forwards DHCP requests to the DHCP server (Switch B) after replacing Option 82 in the 

requests, so that the DHCP clients can obtain IP addresses. 

# Specify IP addresses for the interfaces (omitted). 

# Enable DHCP. 

<SwitchA> system-view 

[SwitchA] dhcp enable 

# Add DHCP server 10.1.1.1 into DHCP server group 1. 

[SwitchA] dhcp relay server-group 1 ip 10.1.1.1 

# Enable the DHCP relay agent on VLAN-interface 1. 

[SwitchA] interface vlan-interface 1 

[SwitchA-Vlan-interface1] dhcp select relay 

# Correlate VLAN-interface 1 to DHCP server group 1. 

[SwitchA-Vlan-interface1] dhcp relay server-select 1 

# Enable the DHCP relay agent to support Option 82, and perform Option 82-related configurations. 

[SwitchA-Vlan-interface1] dhcp relay information enable 

[SwitchA-Vlan-interface1] dhcp relay information strategy replace 

[SwitchA-Vlan-interface1] dhcp relay information circuit-id string company001 

[SwitchA-Vlan-interface1] dhcp relay information remote-id string device001