What Is administrative distance

Administrative distance is the feature that routers use in order to select the best path when there are two or more different routes to the same destination from two different routing protocols. Administrative distance defines the reliability of a routing protocol. Each routing protocol is prioritized in order of most to least reliable with the help of an administrative distance value.

The table bellow lists the administrative distance default values used by Cisco.

Route Source

Default Distance

Connected interface

0

Static route

1

Enhanced Interior Gateway Routing Protocol (EIGRP) summary route

5

External Border Gateway Protocol (BGP)

20

Internal EIGRP

90

IGRP

100

OSPF

110

Intermediate System-to-Intermediate System (IS-IS)

115

Routing Information Protocol (RIP)

120

Exterior Gateway Protocol (EGP)

140

On Demand Routing (ODR)

160

External EIGRP

170

Internal BGP

200

Unknown*

255

* If the administrative distance is 255, the router does not install the route in the routing table.


Vulnerability Announcements
Multiple Vulnerabilities in Cisco Unified IP Phones 7900 Series

Default Credentials Vulnerability in Cisco Network Registrar

Cisco RVS4000 and WRVS4400N Web Management Interface Vulnerabilities

Cisco Content Services Gateway Denial of Service Vulnerability

Multiple Vulnerabilities in Cisco AnyConnect Secure Mobility Client

Cisco SA 500 Series Security Appliances Web Management Interface Vulnerabilities

Cisco ASR 9000 Series Routers Line Card IP Version 4 Denial of Service Vulnerability

Field Notices
(Cisco CRS Series Routers) Field Notice: FN - 63126 - CRS: 1OC768-ITU/C cards may experience High Bit Error Rate (BER) or loss of Transmit power incidents in certain batch of optical module - Workaround Fix on Failure

(Cisco CRS Series Routers) Field Notice: FN - 63046 - CRS - 1OC768-POS-SR cards May Experience Bit Error Rate (BER) Incidents Due to Onboard Short - Fix on Failure

(Cisco MGX 8800 Series Switches) Field Notice: FN - 63319 - MGX - VXSM-SW May Report Error Code 400 for CAS Signaling Call - Workaround Available

(Cisco 7800 Series Media Convergence Servers) Field Notice: FN - 63324 - A Limited Number of HP DL380-G6 Servers Shipped Prior to November 16, 2009 May Unexpectedly Reboot

(Cisco 800 Series Routers) Field Notice: FN - 63343 - PCEX-3G-HSPA-R6 Modem not Recognized in Cisco IOS 15.1(1)T of Cisco 880G Series Router - Cisco IOS Upgrade Required

(Cisco MDS 9500 Series Multilayer Directors) Field Notice: FN - 63132 - MDS9000 - Potential DIMM Memory Issue in a Small Number of DS-X9530-SF2-K9 Supervisor Cards Manufactured Between September 2007 and February 2008