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Cisco ASA Series CLI Configuration Guide
Chapter 1 Routing Overview
Information About the Routing Table
•
Dynamic Routing in Multiple Context Mode, page 1-10
Displaying the Routing Table
To view the entries in the routing table, enter the following command:
hostname#
show route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is 10.86.194.1 to network 0.0.0.0
S 10.1.1.0 255.255.255.0 [3/0] via 10.86.194.1, outside
C 10.86.194.0 255.255.254.0 is directly connected, outside
S* 0.0.0.0 0.0.0.0 [1/0] via 10.86.194.1, outside
On the ASA 5505, the following route is also shown. It is the internal loopback interface, which is used
by the VPN hardware client feature for individual user authentication.
C 127.1.0.0 255.255.0.0 is directly connected, _internal_loopback
How the Routing Table Is Populated
The ASA routing table can be populated by statically defined routes, directly connected routes, and
routes discovered by the RIP, EIGRP, and OSPF routing protocols. Because the ASA can run multiple
routing protocols in addition to having static and connected routes in the routing table, it is possible that
the same route is discovered or entered in more than one manner. When two routes to the same
destination are put into the routing table, the one that remains in the routing table is determined as
follows:
•
If the two routes have different network prefix lengths (network masks), then both routes are
considered unique and are entered into the routing table. The packet forwarding logic then
determines which of the two to use.
For example, if the RIP and OSPF processes discovered the following routes:
–
RIP: 192.168.32.0/24
–
OSPF: 192.168.32.0/19
Even though OSPF routes have the better administrative distance, both routes are installed in the
routing table because each of these routes has a different prefix length (subnet mask). They are
considered different destinations and the packet forwarding logic determines which route to use.
•
If the ASA learns about multiple paths to the same destination from a single routing protocol, such
as RIP, the route with the better metric (as determined by the routing protocol) is entered into the
routing table.
Summary of Contents for 5505 - ASA Firewall Edition Bundle
Page 28: ...Glossary GL 24 Cisco ASA Series CLI Configuration Guide ...
Page 61: ...P A R T 1 Getting Started with the ASA ...
Page 62: ......
Page 219: ...P A R T 2 Configuring High Availability and Scalability ...
Page 220: ......
Page 403: ...P A R T 2 Configuring Interfaces ...
Page 404: ......
Page 499: ...P A R T 2 Configuring Basic Settings ...
Page 500: ......
Page 533: ...P A R T 2 Configuring Objects and Access Lists ...
Page 534: ......
Page 601: ...P A R T 2 Configuring IP Routing ...
Page 602: ......
Page 745: ...P A R T 2 Configuring Network Address Translation ...
Page 746: ......
Page 845: ...P A R T 2 Configuring AAA Servers and the Local Database ...
Page 846: ......
Page 981: ...P A R T 2 Configuring Access Control ...
Page 982: ......
Page 1061: ...P A R T 2 Configuring Service Policies Using the Modular Policy Framework ...
Page 1062: ......
Page 1093: ...P A R T 2 Configuring Application Inspection ...
Page 1094: ......
Page 1191: ...P A R T 2 Configuring Unified Communications ...
Page 1192: ......
Page 1333: ...P A R T 2 Configuring Connection Settings and QoS ...
Page 1334: ......
Page 1379: ...P A R T 2 Configuring Advanced Network Protection ...
Page 1380: ......
Page 1475: ...P A R T 2 Configuring Modules ...
Page 1476: ......
Page 1549: ...P A R T 2 Configuring VPN ...
Page 1550: ......
Page 1965: ...P A R T 2 Configuring Logging SNMP and Smart Call Home ...
Page 1966: ......
Page 2059: ...P A R T 2 System Administration ...
Page 2060: ......
Page 2098: ...1 8 Cisco ASA Series CLI Configuration Guide Chapter 1 Troubleshooting Viewing the Coredump ...
Page 2099: ...P A R T 2 Reference ...
Page 2100: ......