can more than one protocol be run at the same time on a router

[sonia.j.aditya]

on a network using just ipv4 address can more than one routing protocols be run @ tha same time to reach the same destination using the same path???

[InayathUlla Sharieff · Accepted solution]

Hi Sonia,

Yes you can run multiple routing protocol to reach the same destination . But the path learned via routing protocol with lowest metric/Administrative distance(AD) will be considered as the best path.

More information :

http://docstore.mik.ua/orelly/networking/tcpip/ch04_03.htm

http://www.diablotin.com/librairie/networking/tcpip/ch07_04.htm

HTH

Regards

Inayath

*Plz rate all usefull posts.,

[sonia.j.aditya]

Thanks a ton buddy...

[Bilal Nawaz · Accepted solution]

Yes it is possible - however, only one protocol or static route will determine which is the best path. The protocol with the better AD and metric will make it to the routing table. Others will be ignored unless they are equal of course.

Im going to be cheeky and force this with only one link between 2 routers

I have R1 and R2

From R2 I am advertising 1.1.1.1 towards R1 via OSPF which has an AD of 110.

R1:

Router#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

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets

O       1.1.1.1 [110/11] via 100.0.0.2, 00:00:02, FastEthernet0/0

     100.0.0.0/30 is subnetted, 1 subnets

C       100.0.0.0 is directly connected, FastEthernet0/0

Lets go ahead and enable EIGRP on both routers, same link which has a better AD of 90. I will advertise the 1.1.1.1 network too.

R1:

Router(config)#router eigrp 1

Router(config-router)#network 100.0.0.1 0.0.0.0

Router(config-router)#

*Mar  1 00:06:08.283: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 100.0.0.2 (FastEthernet0/0) is up: new adjacencyend

Router#show ip route

*Mar  1 00:06:11.791: %SYS-5-CONFIG_I: Configured from console by console

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

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets

D       1.1.1.1 [90/409600] via 100.0.0.2, 00:00:05, FastEthernet0/0

     100.0.0.0/30 is subnetted, 1 subnets

C       100.0.0.0 is directly connected, FastEthernet0/0

We can see that the 1.1.1.1 OSPF route has been replaced with the EIGRP route which has the AD of 90.

Router#show ip protocols

Routing Protocol is "ospf 1"

  Outgoing update filter list for all interfaces is not set

  Incoming update filter list for all interfaces is not set

  Router ID 100.0.0.1

  Number of areas in this router is 1. 1 normal 0 stub 0 nssa

  Maximum path: 4

  Routing for Networks:

  Routing on Interfaces Configured Explicitly (Area 0):

    FastEthernet0/0

Reference bandwidth unit is 100 mbps

  Routing Information Sources:

    Gateway         Distance      Last Update

    100.0.0.2            110      00:17:47

  Distance: (default is 110)

Routing Protocol is "eigrp 1"

  Outgoing update filter list for all interfaces is not set

  Incoming update filter list for all interfaces is not set

  Default networks flagged in outgoing updates

  Default networks accepted from incoming updates

  EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5=0

  EIGRP maximum hopcount 100

  EIGRP maximum metric variance 1

  Redistributing: eigrp 1

  EIGRP NSF-aware route hold timer is 240s

  Automatic network summarization is in effect

  Maximum path: 4

  Routing for Networks:

    100.0.0.1/32

  Routing Information Sources:

    Gateway         Distance      Last Update

    100.0.0.2             90      00:15:40

  Distance: internal 90 external 170

Hope this helps

Please rate useful posts and remember to mark any solved questions as answered. Thank you.

[sonia.j.aditya]

Thank you Bilal, really appreciate it.