Dell PowerEdge M420 Dell PowerConnect M8024-k User's Configuration Guide - Page 856
What Are Loopback Interfaces?, security is required.
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traffic between VLANs while still containing broadcast traffic within VLAN boundaries. The configuration of VLAN routing interfaces makes inter-VLAN routing possible. For each VLAN routing interface you can assign a static IP address, or you can allow a network DHCP server to assign a dynamic IP address. When a port is enabled for bridging (L2 switching) rather than routing, which is the default, all normal bridge processing is performed for an inbound packet, which is then associated with a VLAN. Its MAC Destination Address (MAC DA) and VLAN ID are used to search the MAC address table. If routing is enabled for the VLAN, and the MAC DA of an inbound unicast packet is that of the internal router interface, the packet is routed. An inbound multicast packet is forwarded to all ports in the VLAN, plus the internal bridge-router interface, if it was received on a routed VLAN. Since a port can be configured to belong to more than one VLAN, VLAN routing might be enabled for all of the VLANs on the port or for only some of the VLANs on the port. VLAN Routing can be used to allow more than one physical port to reside on the same subnet. It could also be used when a VLAN spans multiple physical networks, or when additional segmentation or security is required. What Are Loopback Interfaces? A loopback interface is a logical interface that is always up and, because it cannot go down, allows the switch to have a stable IP address that other network devices and protocols can use to reach the switch. The loopback can provide the source address for sent packets. NOTE: In this context, loopback interfaces should not be confused with the loopback IP address, usually 127.0.0.1, assigned to a host for handling self-routed packets. The loopback interface does not behave like a network switching port. Specifically, there are no neighbors on a loopback interface; it is a pseudodevice for assigning local addresses so that the other layer 3 devices can communicate with the switch by using the loopback IP address. The loopback interface is always up and can receive traffic from any of the existing active interfaces. Thus, given reachability from a remote client, the address of the loopback can be used to communicate with the switch through various 856 Configuring Routing Interfaces
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1,187
-
1,188
-
1,189
-
1,190
-
1,191
-
1,192
-
1,193
-
1,194
-
1,195
-
1,196
-
1,197
-
1,198
-
1,199
-
1,200
-
1,201
-
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
-
1,235
-
1,236
-
1,237
-
1,238
-
1,239
-
1,240
-
1,241
-
1,242
-
1,243
-
1,244
-
1,245
-
1,246