Owners manual

DGS-1510 Series Gigabit Ethernet SmartPro Switch CLI Reference Guide
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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.
Example
This example shows how a DHCP relay pool “pool1” is created. In the relay pool, the subnet
172.19.10.0/255.255.255.0 is specified as the source subnet and 10.2.1.1 is specified as the relay
destination address.
Switch# configure terminal
Switch(config)# ip dhcp pool pool1
Switch(config-dhcp-pool)# relay source 172.19.10.0 255.255.255.0
Switch(config-dhcp-pool)# relay destination 10.2.1.1
Switch(config-dhcp-pool)#
16-20 relay source
This command is used to specify the source subnet of client packets. Use the no form of command to
remove the source subnet
relay source IP-ADDRESS SUBNET-MASK
no relay source IP-ADDRESS SUBNET-MASK
Parameters
IP-ADDRESS
Specifies the source subnet of client packets.
SUBNET-MASK
Specifies the network mask of the source subnet.
Default
None.
Command Mode
DHCP Pool Configuration Mode.
Command Default Level
Level: 12.
Usage Guideline
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. 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