Archive : Cisco-routing

Port-channel (or etherchannel) is a great way to increase the transport capacity between 2 switches or between a switch and an end device that suport load balancing (e.g. server). Today I don’t want to focus on how the Port-channel are configured, but more on how they load-balance the traffic over...

Let’s assume that you have a Cisco router with 2 ISP connection. The first one it’s a 10Mbps connection with a decent latency and the second one it’s a 2Mbps connection with quite high latency. Since you don’t want to load balance over this 2 connections for the obvious reasons...

In this post I proposed to discuss a little bit about Hot Standby Router Protocol and how it can be configured on a Cisco device. For this I have chosen the following topology:I had in mind this scenario due to the fact that the traffic can take multiple paths in case of link being down and this give...

I believe most of you are familiar how OSPF is injecting a default route in a normal area. If not, you can find here all the documentation that you need. Please be familiar with this concept before reading this article. Now, let’s assume that we have the following topology (click on image to have...

The title actually was a request that I encounter during my CCIE RS preparation. Of course, that in the real world, I would go straight forward and implement an access-list do drop selected packets. But since the lab environment is different for the real one, you might get a task like the above one. Let’s...

I was explaining in the previous post what is the difference between optimal and suboptimal path and how to avoid the use of not such a good path in your routed environment. Also there I presented this so call “dirty trick” you can use to force the routing protocol to choose the path that...

Everywhere in the world people try to find the optimal path to achieve something.If we speak about roads, trips and in our case networking, choosing the best path to an end point can have only advantages. I took the term optimal / suboptimal path from the routing issues that can appear in the OSPF network...

Cisco Policy Based Routing provides a flexible mechanism for network administrators to customize the operation of the routing table and the flow of traffic within their networks. Policy Based Routing (PBR) offers many advanced features, including selection and forwarding of traffic to discreet Virtual...