D-Link DXS-3600 Series Cli Reference Manual page 339

DXS-3600 Series Layer 3 Managed 10Gigabit Ethernet Switch CLI Reference Guide
relay source IP-ADDRESS SUBNET-MASK
no relay source IP-ADDRESS SUBNET-MASK
Parameters
IP-ADDRESS
SUBNET-MASK
Default
None.
Command Mode
DHCP Pool Configuration Mode.
Command Default Level
Level: 12.
Usage Guideline
In addition to relay DHCP packets based on the ip helper-address command, the relay destination of
DHCP server can be specified in DHCP relay pool. To do this, use the ip dhcp pool command to enter
the DHCP pool configuration mode, use the relay source command to specify the source subnet of the
client requests and use the relay destination command to specify the relay destination server address.
Multiple relay sources and multiple relay destinations can be specified in a pool. If a packet matches
anyone of the relay source, the packet will be forwarded to all of the relay destinations.
When receiving a DHCP request packet, if the subnet of the received packet matches the rely source of a
relay pool, the packet will be relayed based on this relay pool. Otherwise, the packet is relayed based on
the IP helper address configured on the received interface. To relay a packet based on the relay pool, if
the request packet is a relayed packet, the GIADDR of the packet is the source of the request. If the
request packet is not a relayed packet, the subnet of the received interface is the source of the packet.
In a DHCP relay pool, administrators can further use the class command and the relay target command
to associate a list of relay target addresses with a DHCP class. The DHCP packet will not be relayed, if
the interface that receives the packet has no IP address configured.
Example
This example shows how a DHCP relay pool "pool2" is created. In the relay pool, the subnet
172.19.18.0.0/255.255.255.0 is specified as the source subnet and 10.2.1.10 is specified as the relay
destination address.
Switch# configure terminal
Switch(config)# ip dhcp pool pool2
Switch(config-dhcp-pool)# relay source 172.19.18.0 255.255.255.0
Switch(config-dhcp-pool)# relay destination 10.2.1.10
Switch(config-dhcp-pool)#
21-15 relay target
This command is used to specify a DHCP relay target for relaying packets that matches the value pattern
of the option defined in the class. Use the no form of the command to delete a relay target.
relay target [vrf VRF-NAME | global] IP-ADDRESS
no relay target [vrf VRF-NAME | global] IP-ADDRESS
Specifies the source subnet of client packets.
Specifies the network mask of the source subnet.
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