GNS3 LAB Cisco : EVPN (BGP/MPLS) IRB (integrated routing and bridging) Configuration and Verification.

So far we have seen EVPN single home and EVPN multihome setup and configuration with Cisco csr1000v router. You can find the links for those posts below. EVPN -Single home GNS3 LAB Cisco : BGP-EVPN Single Home Configuration EVPN -Multi homeGNS3 Lab Cisco : EVPN Multihome Concept and Configurations Note : As per Cisco docs… Read More GNS3 LAB Cisco : EVPN (BGP/MPLS) IRB (integrated routing and bridging) Configuration and Verification.

November 5, 2021November 5, 2021 shambhucompLeave a comment

Cisco IOS IP NAT Trouble Ticket 2

In continuation of my last post Trouble Ticket 1 , following is another trouble ticket related to NAT. Please find the details below : Task : In this example we have configured NAT on SITE1 router to translate hosts going out from inside network. This is simplest for of NAT but for some reason the… Read More Cisco IOS IP NAT Trouble Ticket 2

May 5, 2018May 23, 2018 shambhucompLeave a comment

Cisco IOS IP NAT Trouble Ticket 1

NAT (Network Address Translation) is widely used technology which solves many problems like enabling internal hosts(private IP address range) to communicate with outer world, adding an extra security layer by hiding internal IP address etc. In this blog post I am going to discuss a small but widely common NAT issue. Please see the following… Read More Cisco IOS IP NAT Trouble Ticket 1

April 27, 2018May 23, 2018 shambhucomp1 Comment

Script : SSH into Cisco router with Python

Network programming is now becoming a necessary skill for Network engineers. You can no more become a good network engineer without Network programming skills. Things are getting changed on daily basis, every now and then we see new tools being introduced to automate boring and redundant things. There is a whole industry out there which… Read More Script : SSH into Cisco router with Python

April 24, 2018August 22, 2019 shambhucomp1 Comment

Configuring SSH on Cisco devices

There are multiple methods to manage a device like TELNET, SNMP, NETCONF, REST API,HTTP,HTTPS etc . But I think SSH by far is most standard and robust to method. Unlike telnet SSH uses TCP to initiate the connection between the server and client.Once the three way handshake is done basically three steps occur to exchange… Read More Configuring SSH on Cisco devices

April 20, 2018May 23, 2018 shambhucompLeave a comment

Using SNMP to download running-configuration from Cisco router via SCP

We know that SNMP can be used for many tasks apart from monitoring. One of them is to download configuration from the networking device. For this purpose we use SNMP SET commands to set the required variables on the router and then trigger the download. In this blog I will concentrate on SCP(Secure copy) as… Read More Using SNMP to download running-configuration from Cisco router via SCP

April 19, 2018May 23, 2018 shambhucompLeave a comment

MPLS QOS

In my previous post I have setup a very basic MPLS network. I will use the same setup to explain how exactly MPLS ensures QOS for packets which hit MPLS domain with a tag. Following is the process which occurs when the plane IP packet enters the MPLS domain. Tags available in the IP field… Read More MPLS QOS

April 18, 2018May 23, 2018 shambhucompLeave a comment

Question : Why all other areas must be connected to ospf area 0(backbone)?

What I have read and know till now is since ospf behaves like distance vector protocol for inter area communication hence it is vulnerable to routing loops that’s why all the ABRs must be connected to ospf area0 and interarea communication happens through backbone area ….but you may ask that how distance vector in inter… Read More Question : Why all other areas must be connected to ospf area 0(backbone)?

July 20, 2015May 23, 2018 shambhucompLeave a comment

OSPF : Few basic questions…

On this blog I would like to discuss few basic details of ospf which everybody needs to know and which is very helpful to build the concepts of OSPF. For this we are going to use below reference GNS 3 topology. Question 1 : How and when the information about the ABR and ASBR is… Read More OSPF : Few basic questions…

July 20, 2015May 25, 2018 shambhucompLeave a comment