EIGRP HSRP dilemma

Answered Question
Jan 30th, 2007

I have 4 routers on one ethernet media. Two routers works in kind of pair and should be backup for each other. Now I have dilemma. Should I use EIGRP and have 4 EIGRP neighbours or .... can I put two routers in HSRP and then use HSRP virtual address as EIGRP neighbour? What is better?

thanks

I have this problem too.
0 votes
Correct Answer by Richard Burts about 9 years 7 months ago

Dragan

No you can not. EIGRP will form neighbor relationships on the physical (local) address and EIGRP will NOT use the HSRP virtual address.

I am not clear what your environment is and what you are trying to accomplish. But if you want 2 of the routers to talk to each other and not to the other 2 routers, there is a simple solution. Configure 2 of the routers with one AS number and configure the other 2 with a different AS number. Routers on the same segment running EIGRP with different AS numbers will not become neighbors and will not exchange routing updates.

HTH

Rick

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (2 ratings)
Loading.
vijayasankar Tue, 01/30/2007 - 22:27

Hi,

You should always run the routing protocol between all participating Routers.

Let us know more about your network and what you are trying to achieve

-VJ

dragec Tue, 01/30/2007 - 23:36

I am trying to find out if I could benefit from using HSRP virtual address as source for EIGRP.

thanks!

Correct Answer
Richard Burts Wed, 01/31/2007 - 03:55

Dragan

No you can not. EIGRP will form neighbor relationships on the physical (local) address and EIGRP will NOT use the HSRP virtual address.

I am not clear what your environment is and what you are trying to accomplish. But if you want 2 of the routers to talk to each other and not to the other 2 routers, there is a simple solution. Configure 2 of the routers with one AS number and configure the other 2 with a different AS number. Routers on the same segment running EIGRP with different AS numbers will not become neighbors and will not exchange routing updates.

HTH

Rick

mheusinger Wed, 01/31/2007 - 04:05

Hi Rick,

basically with two AS numbers the network would be split into two parts not able to exchange routing info other than through redistribution. And I think you would agree not to opt for such a solution if other options exist because of the likelyness of routing loops.

So the two options I would consider are

1) EIGRP with one AS on all 4 routers

2) HSRP plus static routing

The first option is straight forward, easy to configure and unless other/additional requirements are presented what I would implement.

The second option requires to use static routing to the opposite HSRP next hop from both sides. Should also work, but requires more administrative attention in case new networks are introduced.

Regards, Martin

Richard Burts Wed, 01/31/2007 - 07:41

Martin

As I said in my post I think that we need a better understanding of what Dragan is wanting to accomplish. Based on this sentence: "Two routers works in kind of pair and should be backup for each other" I assume that he does not want all 4 routers to share advertisements with each other. And that is why I suggested 2 different AS be used. That would allow each pair of routers to work together and to back each other up but not to share advertisements with the other pair.

But we really do not know what Dragan wants to accomplish. And till we do know there are lots of possibilities to consider.

HTH

Rick

mheusinger Wed, 01/31/2007 - 07:45

True Rick,

sorry for the misunderstanding. Did not want to attack you. [Edit on] Did not want to be unpolite [Edit off].

Just having sometimes problems to get the right dosis of fine tuning into my English, being non native speaker.

Regards, Martin

Richard Burts Wed, 01/31/2007 - 09:18

Martin

No Problem. I do not feel attacked or any lack of politeness. And I sympathesize with the difficulty of communicating in a language which is not your native language. And I suspect that language differences are part of the reason that we each picked different parts of the original post as guiding our responses.

Occasional differences of opinion keep the forum interesting and frequently point out that there may be more than one viable solution.

Keep up the good work.

HTH

Rick

devang_etcom Wed, 01/31/2007 - 11:12

hi rick and martin,

issue is not language... but most important part is both of you tried to solve the problem... if found both you people on the same disscussion forum since i join this forum... and definetly both of you people had resovle the lots of post... and i do have lots of respect for you as well as all of the Netpro experts and member... this forum keep every one update and also save from the boss attack :) ...

and even lots of time i learned and improve my mistakes from this forum and still doing the same thing... and CISCO is like open sky... as you try to go in deep its become more and more deeper... so definelty my big respect to CISCO also...

regards

Devang

Actions

This Discussion