cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
1895
Views
0
Helpful
9
Replies

BGP Edge router - BGP route summary

AmandaBrown2015
Level 1
Level 1

Can someone please assist me with this issue?

I have an internet edge router and do not want to receive the full BGP table from the internet.

What is the best way to go? e.g best practices.

my next hop is my ISP using a /30 ip address

Thank you

9 Replies 9

Hello,

Are you an ISP or an end user. If you are only an end user, you can ask your ISP to send you a default route.

Masoud

I am an end user

Thank you

Receiving a default route is suggested if you are an end user. In this way, you do not have to deal with so many routes which consume memory and need administration. ISPs are usually willing to send you a default route as opposed to full internet routes. You might implement filtering as others suggested to prevent adding wrong routes to the routing table in case of misconfiguration. Having another link to another ISP is also recommented in order to avoid single link failure.

Masoud

Thank you very much Masoud

You are very welcome. Have a good Thanksgiving.

Masoud

Hello

Below would a very basic example of an bgp peering to an Isp

With in/outbound filtering.obviously you can amend to this to suit your needs

Ip as-path access-list permit ^$

ip prefix-list default permit 0.0.0.0/0

Router bgp xx

no auto-summary

no synchroniszation

Neighbor x.x.x.x remote-as ISP (peer to ISP)

Neighbor x.x.x.x password xxxx ( basic authentication)

Neighbour x.x.x.x prefix-list default in ( accept default only)

Neigbour x.x.x.x filter-list 10 out ( advertise only local routes)

res

paul


Please rate and mark as an accepted solution if you have found any of the information provided useful.
This then could assist others on these forums to find a valuable answer and broadens the community’s global network.

Kind Regards
Paul

Thank you very much Paul!

I really appreciate the response!

Vinit Jain
Cisco Employee
Cisco Employee

You can do couple of things in this case:

- You can ask your ISP to not send the whole Internet Routing table but a default route for Internet connectivity.

- if that is not possible, then you can perform route filtering on your router permitting only those prefixes that you need in your network.

Hope this helps

Regards

Vinit

Thanks
--Vinit

Hi,

I'd rephrase:

...

- if that is not possible, then you can perform route filtering on your router denying all prefixes received from the ISP and configure a static default route on your router pointing to your ISP router IP address as the next-hop.

BR,

Milan

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Review Cisco Networking products for a $25 gift card