Installation guide

Cisco AS5850 Universal Gateway Commissioning Guidelines

78-10537-04

How to Commission the Cisco AS5850 Universal Gateway

Configure Basic IP

To configure a basic dial-access service of two loopback interfaces, bring up one Fast Ethernet interface,

and add an IP route to the default gateway, perform the following steps.

Step 1 Assign the IP addresses and create an IP route to the default gateway.

interface Loopback0

ip address 172.22.99.1 255.255.255.0

interface Loopback1

ip address 172.22.90.1 255.255.255.0

interface FastEthernet0/1/0

ip address 172.22.66.23 255.255.255.0

ip route 0.0.0.0 0.0.0.0 172.22.66.1

The advantage of assigning a gateway’s IP address to a loopback rather than a physical interface is that

a loopback interface never goes down. The roles of the two loopback interfaces is as follows:

• interface Loopback0 identifies the gateway with a unique and stable IP address for

network-management purposes. Assigning one IP address from a common address block to each

network device enables the network operations center to more easily perform security filtering.

• interface Loopback1 hosts a pool of IP addresses for the remote nodes. Thus, one route is

summarized and propagated to the backbone instead of 254 host routes.

Step 2 Verify that the Fast Ethernet interface is up by pinging the default gateway.

Gateway# ping 172.22.66.1

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 172.22.66.1, timeout is 2 seconds:

.!!!!

Success rate is 80 percent (4/5), round-trip min/avg/max = 1/1/1 ms

Gateway#

This step verifies that you have IP connectivity with another device on the subnet. If the ping succeeds

to the default gateway, try pinging the DNS server in your backbone. Make sure the backbone is

configured to get to the universal gateway; otherwise, the ping does not work. Configure the backbone

gateways to support the routes to the networks that you are using.

Note An 80% ping-success rate is normal the first time you ping an external device. The universal

gateway does not yet have an address-resolution-protocol (ARP) entry for the external device.

A 100% success rate should result the next time you ping the device.