Topology changes in a spanning-tree domain are inevitable. But what actually happens, and what impact does it have on the environment? We will find it out in this article! Topology We will examine today’s scenarios on the 3-tier topology. We’ve
Category: GNS3
PVST and MST (in)compatibility
Spanning-tree protocol configurations can cause headaches among network engineers. Especially if we have mixed topology, with more than one STP implementation. In this article, we will look closer at the interoperability between the Cisco PVST and MST. Based on two
How to add and configure Nokia VSR VM in the GNS3
GNS3 is a powerful tool to simulate computer networks. Many images are ready to use right after the basic setup. However, sometimes we have to put in some more work to make everything work as expected. In this article, we
OSPF with BFD case study
While administrating the network, it’s important to think about high availability. If one network element goes down, the network can still operate properly after it’s converged. But how about the convergence time? It differs from one protocol to another, and
IPv6 tunneling over IPv4 GRE
As network engineers, sometimes we have to deal with unusual problems. One of them is when we have two isolated IPv6 network parts, but we want them to be able to communicate with each other. In this article, we’re gonna
Layer 3 MTU case study
In the previous article, I’ve touched the layer 2 MTU topic. This time, we will see how’s the behaviour of layer 3 MTU in 3 different scenarios. Packet structure First of all, before we touch on some case scenarios, let’s
Layer 2 MTU case study
The MTU topic seems to be confusing, especially among young network engineers. I’ve decided to into two parts. This article is focused on the layer 2 MTU aspect exclusively. I’ve prepared 3 case scenarios to present how’s switch behaves with
MST interoperability between Nokia 7750 and Cisco IOS
In this article, I want to briefly touch on the Multiple Spanning Tree protocol configuration on Nokia 7750 and its compatibility with Cisco equipment. The spanning-tree configuration on SR-OS varies by type. The MST is slightly different because it uses
Routed VPLS
In this article, I want to shed some light on the configuration of routed VPLS’es on Nokia 7750 equipment. The basic VPLS configuration allows only communication between hosts within that VPLS. Sometimes there is a need to provide communication between
Bridging different VLANs on the Nokia VSR
In the previous article, I’ve shown how to configure layer 2 connectivity between the Cisco switch and Nokia router. There are however situations when you will be forced to find a non-standard solution due to the circumstances. Imagine the following