Loopback Interfaces - Dell PowerConnect M6220 Configuration Manual

An ECMP route contains only next hops whose paths to the destination are of equal cost. Referring to
Figure 4-8, if OSPF were configured on all links, but Router A's interface to the 10.1.1.x network had an
OSPF link cost of 5 and its interface to the 10.1.2.x network had an OSPF link cost of 10, then OSPF
would use only 10.1.1.2 as the next hop to 20.0.0.0/8.
Example 1: Configuring an ECMP Route
In the following example, two static routes to the same destination are configured to use different next
hops (e.g., for load balancing purposes). Note that the preference metric is not specified, so both routes
assume the default static route preference of 1.
console#Config
ip route 20.0.0.0 255.0.0.0 10.1.1.2
ip route 20.0.0.0 255.0.0.0 10.1.2.2
exit
The following command adds a third route with a preference value of 5. This route will be used only
when the first two are unreachable:
ip route 20.0.0.0 255.0.0.0 10.1.3.2 5

Loopback Interfaces

PowerConnect 6200 Series software provides for the creation, deletion, and management of loopback
interfaces.
A loopback interface is a software-only interface that is not associated with a physical location; as such it
is not dependent on the physical status of a particular router interface and is always considered "up" as
long as the router is running. It enables configuring a stable IP address for remote clients to refer to. The
client can communicate with the loopback interface using any available, active router interface.
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.
Loopbacks are typically used for device management purposes. A client can use the loopback interface to
communicate with the router through various services such as telnet and SSH. The address on a
loopback behaves identically to any of the local addresses of the router in terms of the processing of
incoming packets. This interface provides the source address for sent packets and can receive both local
and remote packets.
NOTE:
The following example uses the CLI to configure a loopback interface. You can also use the Web interface.
Click Routing > Loopbacks in the navigation tree.
You can create a loopback interface in the Global Config mode by assigning it a unique ID from 0 to 7:
console#configure
console(config)#interface loopback 0
Next, you assign an IPv4 or IPv6 address to the interface:
console(config-if-loopback0)#ip address 192.168.1.2 255.255.255.255
Routing Configuration
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