Specifications

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Cisco AS5800 Operations, Administration, Maintenance, and Provisioning Guide
DOC-7810814=
Chapter 2 Commissioning
Task 2. Configuring Basic Cisco IOS Software
Configuring Basic IP
To configure a basic dial access service:
• Configure two loopback interfaces.
• Bring up one Fast Ethernet interface.
• Add an IP route to the default gateway.
Follow this procedure:
Step 1 Assign the IP addresses, and create an IP route to the default gateway.
!
interface Loopback0
ip address 172.22.99.1 255.255.255.255
!
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 loopback interfaces are used for the following reasons:
• Interface loopback 0:Identifies the router with a unique and stable IP address for network
management purposes. One IP address from a common address block is assigned to each network
device. This technique enables the network operations center (NOC) to more easily perform security
filtering. One class C subnet, that was used to identify devices, can support 254 distinct nodes with
unique loopback IP addresses.
• Interface loopback 1:Hosts a pool of IP addresses for the remote nodes. In this way, one route is
summarized and propagated to the backbone instead of 254 host routes.
Step 2 Verify that the Fast Ethernet interface is up. Ping the default gateway.
5800-NAS# 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
5800-NAS#
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 access server; otherwise, the ping will not work. Configure the backbone routers
to support the routes to the networks you are using.
Note An 80% ping-success rate is normal for the first time you ping an external device.
The NAS does not yet have an address resolution protocol (ARP) entry for the
external device. A 100% success rate is achieved the next time you ping the device.