Posts Tagged ‘election’

Nov
24

Tonight I’m posting some updates to the IEWB-RS Volume 1 Version 5.0 section of OSPF, along with an interesting teaser on how OSPF path selection works towards external routes originated in an NSSA. In my pursuit of networking Nirvana, I have a motto; learn something new every day. This topic for sure will fall into that category for many engineers.

We all (hopefully) know what an NSSA is in OSPF. It’s that cute little area that’s sort of stubby, but not completely, which allows us to cut down on the size of the OSPF database while still doing redistribution into an area. What is a little lesser known fact however, is how calculation towards an external route originated in an NSSA differs from a normal route redistributed into OSPF. Check the above link for the detailed walkthrough of how this works, along with the diagram and initial configs for those of you that don’t already have a subscription to the product, but the spirit of the situation is as follows… Continue Reading

Tags: , , , , ,

Nov
04

I’m currently working on a new design for a customer network, and am trying to decide which routing protocol to migrate to. Brian Dennis mentioned to me that some type of election is going on today… so I decided to have an election of my own!

What is your favorite routing protocol?

  • Scott Morris (38%, 195 Votes)
  • OSPFv2 (21%, 111 Votes)
  • BGP (12%, 60 Votes)
  • EIGRP (11%, 56 Votes)
  • OSPFv3 (6%, 29 Votes)
  • IS-IS (4%, 20 Votes)
  • Static Routing Protocol Version 2 (3%, 16 Votes)
  • Routing Is Overrated – SR/TLB! (2%, 9 Votes)
  • ODR! (1%, 6 Votes)
  • RIPv2 (1%, 5 Votes)
  • EIGRPv6 (1%, 4 Votes)
  • EGP (0%, 2 Votes)
  • Policy Routing (0%, 2 Votes)
  • RIP (0%, 2 Votes)
  • RIPng (0%, 1 Votes)
  • IGRP (0%, 0 Votes)

Total Voters: 518

Loading ... Loading ...

Update: Thanks for all your feedback! Based on everyone’s overwhelming response we’ve decided to implement Scott Morris routing, as follows:

Rack1R1(config)#scott-morris unicast-routing
Rack1R1(config)#router scott
Rack1R1(config-router)#version 6
Rack1R1(config-router)#network 0.0.0.0
Rack1R1(config-router)#end
Rack1R1#
*Jan 17 09:06:53.718: %SYS-5-CONFIG_I: Configured from console by console
Rack1R1#show ip route
Codes: C - connected, S - static, 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
       i - IS-IS, su - IS-IS summary, 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, SM - Scott Morris

Gateway of last resort is not set

SM    204.12.1.0/24 [10/2] via 155.1.0.4, 00:00:00, Serial0/0
     155.1.0.0/24 is subnetted, 10 subnets
C       155.1.146.0 is directly connected, FastEthernet0/0
SM       155.1.23.0 [10/1] via 155.1.13.3, 00:00:08, Serial0/1
C       155.1.13.0 is directly connected, Serial0/1
C       155.1.0.0 is directly connected, Serial0/0
SM       155.1.7.0 [10/2] via 155.1.13.3, 00:00:08, Serial0/1
SM       155.1.58.0 [10/1] via 155.1.0.5, 00:00:00, Serial0/0
SM       155.1.45.0 [10/1] via 155.1.0.5, 00:00:01, Serial0/0
SM       155.1.37.0 [10/1] via 155.1.13.3, 00:00:00, Serial0/1
SM       155.1.79.0 [10/2] via 155.1.13.3, 00:00:00, Serial0/1
SM       155.1.67.0 [10/2] via 155.1.13.3, 00:00:00, Serial0/1
SM    192.10.1.0/24 [10/2] via 155.1.13.3, 00:00:00, Serial0/1  

Rack1R1#show ip route scott
SM    204.12.1.0/24 [10/2] via 155.1.0.4, 00:00:03, Serial0/0
     155.1.0.0/24 is subnetted, 10 subnets
SM       155.1.23.0 [10/1] via 155.1.13.3, 00:00:04, Serial0/1
SM       155.1.7.0 [10/2] via 155.1.13.3, 00:00:04, Serial0/1
SM       155.1.58.0 [10/1] via 155.1.0.5, 00:00:03, Serial0/0
SM       155.1.45.0 [10/1] via 155.1.0.5, 00:00:03, Serial0/0
SM       155.1.37.0 [10/1] via 155.1.13.3, 00:00:04, Serial0/1
SM       155.1.79.0 [10/2] via 155.1.13.3, 00:00:04, Serial0/1
SM       155.1.67.0 [10/2] via 155.1.13.3, 00:00:04, Serial0/1
SM    192.10.1.0/24 [10/2] via 155.1.13.3, 00:00:04, Serial0/1
                   [10/2] via 155.1.0.2, 00:00:03, Serial0/0
     150.1.0.0/24 is subnetted, 6 subnets
SM       150.1.7.0 [10/2] via 155.1.13.3, 00:00:04, Serial0/1
SM       150.1.5.0 [10/1] via 155.1.0.5, 00:00:03, Serial0/0
SM       150.1.4.0 [10/2] via 155.1.0.4, 00:00:03, Serial0/0
SM       150.1.3.0 [10/1] via 155.1.13.3, 00:00:04, Serial0/1
SM       150.1.2.0 [10/2] via 155.1.13.3, 00:00:04, Serial0/1
                  [10/2] via 155.1.0.2, 00:00:04, Serial0/0

Tags: , ,

Categories

CCIE Bloggers