Cisco
DMVPN – NHRP Mapping Flags
In my 3 part guide for DMVPN where we looked at Phase 1 to 3. I showed some output from the ‘show ip nhrp’ command like the below: In this guide, we will go through what the flags in these Read more…
Cisco
Cisco DMVPN Phase III
Building on from the previous guide on DMVPN Phase 2, we are going to transition from Phase 2 to Phase 3. This is only really relevant if you are doing summarisation at the Hub. Lets remind ourselves of the topology: Read more…
Cisco
Cisco DMVPN Phase II
Building on from the previous guide, we are going to transition from DMVPN Phase 1 to DMVPN Phase 2. This will bring some important improvements and some considerations. Lets remind ourselves of the topology: The Hub is still always going Read more…
Cisco
Cisco DMVPN Phase I
In this guide, we will setup DMVPN Phase 1. In that we have one central hub, with multiple spokes. Spokes will learn about both Hub and other Spoke prefixes via EIGRP. Spoke to Spoke traffic is permitted, however the Hub Read more…
Beginner Tutorial
Cisco Policy Based Routing on L3 Switch
In this guide, I will show how to implement basic Policy Based Routing on a Layer 3 Switch. Here is the topology we will work on: In this scenario, we have two routers connected to a core switch. We then Read more…
Cisco
BGP Conditional Route Advertisement for ISP Failover
When using BGP and peering with multiple ISPs at the edge, you can use a feature within BGP that allows you to advertise networks to a neighbour dependent on the existence of a route in the BGP RIB. This is Read more…
Cisco
Using community values and route maps to create a partial BGP table
When you peer with a Service Provider using BGP. They will likely ask you if you want the full BGP table, a partial table or just a default route. Most devices you have on your companies edge, will not be Read more…
Cisco
Using prefix lists and route maps to create a partial BGP table
When you peer with a Service Provider using BGP. They will likely ask you if you want the full BGP table, a partial table or just a default route. Most devices you have on your companies edge, will not be Read more…
Cisco
Leaking Routes from Global to VRF – BGP
VRFs are an excellent tool for Layer 3 separation on a router. Allowing you to separate routing domains and control where traffic can be routed, much like VLANs on a Switch. VRFs are also required for MPLS L3VPN deployments. There Read more…