I have customer's network that is running BGP between all the routers. He has two 0/0 destinations, both at different locations. Can I install two routes in the BGP table in the backbone so that one 0/0 is preferred and if it is unreacheable the other 0/0 will be used?
the answer is yes both border routers can advertise their own 0.0.0.0/0 in iBGP and one can be preferred by using an higher local preference.
Be aware that the backup route can need to be propagated in the domain because routers will advertise only the best path.
So the recovery time when the the primary default fails is given by the propagation time from the second border router to the Route Reflectors to the all the other routers and the bgp scan time on each router to install the backup route.
Another possibility is to leave the two advertisements with the same attributes: in this case for recursion each router will choice the path to the nearest (as per IGP metric) border router, again in case of failure the other path will propagate and will be installed.
This document gives several answers on frequently asked questions for PFRv3 channel state behavior.
Q1: What are all the channel operational states from a BR (border role) perspective and what are the rules/conditions to be in each st...
The need was to reach an host inside a LAN through a VPN connection managed by the LAN gateway (Cisco 1921).
The LAN gateway performs NAT and there was a dedicate nat rule for the host i wanted to reach through VPN.
I couldn't connect to the hos...
We have 3 identical switches configured by someone else and would like to claim some of the Gigabit ports(G1/G2/G3/G4) for use on servers. When we try to change the wiring and configuration, we run in to connectivity issues. Attached is a des...