Private ip address for ibgp peers. Is it good?

[ddxnet]

Hello,

I have PI addresses /24 ,2 ISP, 2 routers. First router connect to first ISP, and second router to second ISP.

Between 2 routers I have IBGP session via loopback interfaces and there pritvate ip address is used.

Is it correct? What kind of problem can I get in future?

[John Blakley]

Is this on an MPLS network or is it a straight connection. Are the networks that you're advertising only between the two routers or do you peer with your ISP using BGP as well?

[Richard Burts]

Would I be correct in understanding that Vladimir is running IBGP between two of his routers and that traffic between those routers goes through his network (and not through Internet or provider public network)? In that case I do not see any problem with using private addressing for the IBGP peering.

HTH

Rick

[ddxnet]

I use EBGP with my two ISPs as well, and I announce my /24 network in the Internet.

Now I notice only one problem, when I try to ping any host in the Internet from one of my 2 routers, I can't do it if the best route passes through my second router(not straight to ISP), because source address is private address in this case

[Edison Ortiz]

You can source the ping on this router from any other available interface. If you have other interfaces with a valid public IP address, it should work.

[ddxnet]

Ofcourse I can, It's in default. I just wanted to know what type of problem can I get.

[Edison Ortiz]

There shouldn't be any problems as this router is just passing your internal traffic.

The only issue as you noted is with traffic sourced from the internal interface but it is a non-issue for day-to-day operations.

If you have to use services from the internet on this router such as NTP, you can always modify the source IP.

[ddxnet]

I know how to change source ip for ping, but how to do it for other services, to be insured that the router uses "right ip" as a source?

[Richard Burts]

There is not a global setting to set the source address but many of the things that you do on the router allow you to specify a source address (for example there is an optional command in configuring ntp to specify the source address, and similar commands for telnet, ssh, ftp, tftp, and many others).

Another other option that you might consider is to configure address translation on the Internet facing router and translate traffic that originated from your router and is going out to the Internet.

And I would suggest that this discussion is really becoming something different from the original question. The original post asked about using private addressing for the IBGP sessions. Now the discussion is really becoming the use of private addressing on devices that may need to access the public Internet.

HTH

Rick