Posts

How to install and use ripe-stat

This is just a quick guide on how to instal use the ripe-stat to get BGP information and a lot more out of it, its a very helpful tool and you can use the widgets from ripestat, https://stat.ripe.net/widget/list.

How to install the ripe-stat tool

For other methods i.e. using pip:

If all else fails there are other options on:
https://github.com/RIPE-NCC/ripestat-text

if you are still not able to install please let post a comment and I will look to help you.

How to check advertised BGP AS-Path using ripe-stat cli

You can trim the data to get what you want example, if I just want to see the as-path from all the looking glasses which use cogent(as174) I could do the following:

Freeup memory on cisco 6500 router with full BGP route tables

In the olden days, we had to have the soft-reconfig setting on our BGP sessions to accept route updates without reloading the entire BGP table.

This takes up a lot of memory, especially when you have 3 ISP;s connecting with full BGP Tables, In these times where the Internet route table is ~488,000 routes and we accept full tables from multiple providers, we can’t afford the memory usage – and we don’t have to!

Today’s Internet providers support a better idea, route-refresh, effectively doing the same thing without the negative. This feature provides a soft reset mechanism that allows the dynamic exchange of route refresh requests and routing information between BGP peers and the subsequent re-advertisement of the outbound or inbound routing table.

is route-refresh supported on cisco 6500

is route-refresh supported on juniper device

According to the above it sure is supported in fact most devices enable and support this, so if you are memory concoius and you can afford to be without soft-reconfig then route-refresh is sufficient enough. On the 6500 device you will not see the memory free up until the router is rebooted.

why we would use as-override in bgp

A reason to use as-override in bgp. Loop prevention in BGP is done by verifying the AS number in the AS Path. If the receiving router sees its own AS number in the AS Path of the received BGP packet, the packet is dropped. The receiving Router assumes that the packet was originated from its own AS and has reached the same place from where it originated initially.

bgp-as-override

In the above scenario lets say R4 in AS100 is sending routes 100.8.0.0/24 and 10.8.0.0/24 into AS6573 through R1, R3 will see the routes but in order for the routes to be accepted at R5 you will need to enable as-override in bgp configuration on router R3 towards router R5, below is how one would configure this:

Router R3 Cisco Example

Router R3 Juniper Example