EIGRP Manual Summarisation routing table entry

kfarrington · ‎11-05-2003

All,

I have a router which connects to as10, as11, and as13. There are multiple routes in as13 that i want to summarise to as10, and as11, and there is mutual redistribution ocuuring on this router.

Now, when I enter the command ip summary address x.x.x.x x.x.x.x eigrp 10 on the as10 interface and the summary address on the as11 interface (ip summary-address x.x.x.x x.x.x.x as11) this creates a null route in the routing table.

You can see the route in both ASs topolgy tables, BUT, which one is entered into the routing table?

Many thx Indeed,

Ken

ruwhite · ‎11-05-2003

It's going to depend on the version of code you're running, I think. On most current code, it should be the route which makes it into the routing table first. If it's really really new code, it should be the route with the lowest metric, then the route from the lowest EIGRP AS.

You can tell which one is being installed, by the way, by looking at the EIGRP topology table for each process. The route that is installed will have some "normal" feasible distance, and will have some number of successors (I think it should be one). The one that isn't installed should have a feasible distance of infinity (42.xx billion), and it should show 0 sucessors.

:-)

Russ.W

rjackson · ‎11-05-2003

It shouldn't matter. Isn't it just pointing to null0? Its a catch all for the subnets that dont really exist but are in the summary.

kfarrington · ‎11-05-2003

Hi Russboy,

uhmm, thx for that. but I dont see the infinity route, just the two null routes (with no FSs). Ahh, by the way, there is mutual redistribution going on between the two ASs also.

the code and hardware are below.

NXWR1MR15>sh hard

Cisco Internetwork Operating System Software

IOS (tm) MSFC2 Software (C6MSFC2-PSV-M), Version 12.1(8a)E5, EARLY DEPLOYMENT RELEASE SOFTWARE (fc2)

TAC Support: http://www.cisco.com/tac

Compiled Mon 22-Oct-01 23:33 by eaarmas

Image text-base: 0x40008980, data-base: 0x415A4000

ROM: System Bootstrap, Version 12.1(4r)E, RELEASE SOFTWARE (fc1)

BOOTFLASH: MSFC2 Software (C6MSFC2-PSV-M), Version 12.1(8a)E5, EARLY DEPLOYMENT RELEASE SOFTWARE (fc

2)

NYPD1MR15 uptime is 4 weeks, 4 days, 12 hours, 0 minutes

System returned to ROM by power-on

System restarted at 14:44:32 EDT Sat Oct 4 2003

Running default software

cisco Cat6k-MSFC2 (R7000) processor with 491520K/32768K bytes of memory.

Processor board ID SAD0550076R

R7000 CPU at 300Mhz, Implementation 39, Rev 3.3, 256KB L2, 1024KB L3 Cache

Last reset from power-on

X.25 software, Version 3.0.0.

Bridging software.

Primary Rate ISDN software, Version 1.1.

2 FlexWAN controllers (8 T1)(2 HSSI)(2 POS).

4 Virtual Ethernet/IEEE 802.3 interface(s)

4 Serial network interface(s)

2 HSSI network interface(s)

2 Packet over SONET network interface(s)

509K bytes of non-volatile configuration memory.

32768K bytes of Flash internal SIMM (Sector size 512K).

Configuration register is 0x2102 (will be 0x102 at next reload)

NXWR1MR15>sh ip eigrp top 69 155.195.64.0 255.255.224.0

IP-EIGRP topology entry for 155.195.64.0/19

State is Passive, Query origin flag is 1, 1 Successor(s), FD is 3328

Routing Descriptor Blocks:

0.0.0.0 (Null0), from 0.0.0.0, Send flag is 0x0

Composite metric is (3328/0), Route is Internal

Vector metric:

Minimum bandwidth is 1000000 Kbit

Total delay is 30 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

0.0.0.0, from Redistributed, Send flag is 0x0

Composite metric is (3328/0), Route is External

Vector metric:

Minimum bandwidth is 1000000 Kbit

Total delay is 30 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

External data:

Originating router is 155.195.1.165 (this system)

AS number of route is 212

External protocol is EIGRP, external metric is 3328

Administrator tag is 212 (0x000000D4)

NXWR1MR15>

NXWR1MR15>sh ip eigrp top 212 155.195.64.0 255.255.224.0

IP-EIGRP topology entry for 155.195.64.0/19

State is Passive, Query origin flag is 1, 1 Successor(s), FD is 3328

Routing Descriptor Blocks:

0.0.0.0 (Null0), from 0.0.0.0, Send flag is 0x0

Composite metric is (3328/0), Route is Internal

Vector metric:

Minimum bandwidth is 1000000 Kbit

Total delay is 30 microseconds

Reliability is 255/255

Load is 1/255

Minimum MTU is 1500

Hop count is 2

NXWR1MR15>

ruwhite · ‎11-06-2003

Well, I just tried it in the lab, and we don't mark one of the two as infinite in this situation. In your case, the route from AS212 is making it into the routing table, based on the output above.

Another way to tell is to run show ip route 155.195.64.0 255.255.224.0, which should tell you the AS number of the process putting the route in the table.

Russ.W