Cisco ASR900 series is a popular platform in service provider domain. If you remember the famous 7600 platform, ASR 900(ASR903/907and 914) is next generation to it. Majorly these devices are classified as SP access platforms. ASR 903 routers are known for high speed data plane(forwarding) because of the ASIC based data plane architecture. In this … More Cisco ASR 903 Series router ISSU upgrade
We know that for most of the protocols router does not change anything in the IP header unless we have specifically configured the IP header to be changed for example NAT, QOS markings etc. In this and few upcoming posts we will specifically look for packet marking when the IP packet gets translated into MPLS … More MPLS Basic configuration and MPLS QOS
DMVPN or Dynamic multipoint VPN is a widely used technology. In this article I will explain why do we need it and how to configure it. Problem-1 : You have huge number of sites and you add and delete sites on daily basis. You connect those sites with GRE tunnels. Do you think adding and … More Cisco DMVPN Configuration and verification
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 … More Question : Why all other areas must be connected to ospf area 0(backbone)?
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 … More OSPF : Few basic questions…
What is Syslog and logging: Syslog is the client server protocol uses port 514 it can be configured to use TCP but basically it uses UDP and transfer logs in clear text.We can define logging as documenting and storing the triggered events in any technological environment. Stored logs can be used for security investigations, troubleshooting … More General understanding of Syslog
I have this topology along with 6 tasks published in my previous blogs regarding ISIS. Check here , ISIS Blog 1, ISIS Blog 2, ISIS Blog 3 . Now when I have covered the basics of ISIS I feel the need to explain the lab topology and tasks…below is the same ..have fun!! Task … More Cisco ISIS GNS3 lab tasks and few other details ….
ISIS Hello has information like as shown below in screen capture. Below are few of them which are frequently used. Circuit type L1 or L2 or L1 and L2 ? In this case it is L1 and L2 System ID: This 48 bit value is taken from the NET string we entered (49.0001.0000.0001.00) System ID … More ISIS Continued(Wireshark walkthrough)…..