Dell PowerConnect 7048P User Manual - Page 907
Configuring L2 and L3 Relay Features, L2 and L3 Relay Overview, What Is L3 DHCP Relay?
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33 Configuring L2 and L3 Relay Features This chapter describes how to configure the L2 DHCP Relay, L3 DHCP Relay, and IP Helper features on PowerConnect 7000 Series switches. The topics covered in this chapter include: • L2 and L3 Relay Overview • Default L2/L3 Relay Values • Configuring L2 and L3 Relay Features (Web) • Configuring L2 and L3 Relay Features (CLI) • Relay Agent Configuration Example L2 and L3 Relay Overview When a DHCP client and server are in the same IP subnet, they can directly connect to exchange IP address requests and replies. However, buying and maintaining a DHCP server on each subnet can be expensive and is often impractical. The relay features on the PowerConnect 7000 Series switches can help enable communication between DHCP clients and DHCP servers that reside in different subnets. Configuring L3 DHCP relay also enables the bootstrap protocol (BOOTP) relay. What Is L3 DHCP Relay? Network infrastructure devices can be used to relay packets between a DHCP client and server on different subnets. Such a device, an Layer 3 Relay agent, is often a router or L3 switch. The L3 relay agent must have an IP interface on the client subnets and, if it does not have an IP interface on the server's subnet, it should be able to route traffic toward the server's subnet. The PowerConnect DHCP Relay Agent enables DHCP clients and servers to exchange DHCP messages across different subnets. The relay agent receives the requests from the clients, and checks the valid hops and giaddr fields in Configuring L2 and L3 Relay Features 907
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1,202
-
1,203
-
1,204
-
1,205
-
1,206
-
1,207
-
1,208
-
1,209
-
1,210
-
1,211
-
1,212
-
1,213
-
1,214
-
1,215
-
1,216
-
1,217
-
1,218
-
1,219
-
1,220
-
1,221
-
1,222
-
1,223
-
1,224
-
1,225
-
1,226
-
1,227
-
1,228
-
1,229
-
1,230
-
1,231
-
1,232
-
1,233
-
1,234