User Manual

UMN:CLI

SURPASS hiD 6615 S223/S323 R1.5

 

 

 

 

 

i

Before configuring DHCP server or relay, you need to use the service dhcp command first to activate the DHCP function in the system.

8.8.4.1Packet Forwarding Address

A DHCP client sends DHCP_DISCOVER message to a DHCP server. DHCP_DISCOVER message is broadcasted within the network to which it is attached. If the client is on a network that does not have any DHCP server, the broadcast is not forwarded because the switch is configured to not forward broadcast traffic. To solve this problem, you can configure the interface that is receiving the broadcasts to forward certain classes of broadcast to a helper address.

To specify a packet forwarding address, use the following command.

Command

Mode

Description

 

 

 

 

 

Specifies a packet forwarding address. More than one

ip dhcp helper-address A.B.C.D

 

address is possible.

 

Interface

A.B.C.D: DHCP server address

no ip dhcp helper-address

 

Deletes a specified packet forwarding address.

{A.B.C.D all}

 

 

 

 

 

 

i

If a packet forwarding address is specified on an interface, the hiD 6615 S223/S323 will enable a DHCP relay agent.

You can also specify an organizationally unique identifier (OUI) when configuring a packet forwarding address. The OUI is a 24-bit number assigned to a company or organization for use in various network hardware products which is a first 24 bits of a MAC address. If an OUI is specified, a DHCP relay agent will forward DHCP_DISCOVER message to a specific DHCP server according to a specified OUI.

To specify a packet forwarding address with an OUI, use the following command.

Command

 

Mode

Description

 

 

 

 

 

 

 

Specifies a packet forwarding address with an OUI.

ip dhcp oui XX:XX:XX

helper-

 

More than one address is possible.

 

XX:XX:XX: OUI (first 24 bits of a MAC address in the

address A.B.C.D

 

 

 

Interface

form of hexadecimal)

 

 

 

 

 

A.B.C.D: DHCP server address

 

 

 

 

no ip dhcp oui XX:XX:XX

 

 

Deletes a specified packet forwarding address.

[helper-address A.B.C.D]

 

 

 

 

 

 

 

 

 

8.8.4.2Smart Relay Agent Forwarding

Normally, a DHCP relay agent forwards DHCP_DISCOVER message to a DHCP server only with a primary IP address on an interface, even if there is more than one IP address on the interface.

If the smart relay agent forwarding is enabled, a DHCP relay agent will retry sending DHCP_DISCOVER message with a secondary IP address, in case of no response from the DHCP server.

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Siemens S223, S323 user manual Packet Forwarding Address, Smart Relay Agent Forwarding, C.D all