Category: CCIE Weakness

OSPFv3 with Address Family Verification

OSPFv3 with Address Family Verification

There are three different verifications to be done with OSPF depending on if they were done with OSPFv2, traditional OSPFv3, and OPSFv3 with Address Families. I will only cover the checks for OSPFv3 with address families here as the other two options are easy to determine. The OSPFv3 has some quirks that make verification a…

Read More Read More

BGP local-as no-prepend

BGP local-as no-prepend

So it is amazing how something will finally just click. I have done several different labs working with the local-as, no-prepend, replace-as, dual-as and the no-prepend was something I just was not understanding. The purpose of these strings is to allow for conversion of a BGP AS number with clients where you can modify or…

Read More Read More

iBGP and Next Hop

iBGP and Next Hop

I have the hardest issue with next-hop-self. This is a very crucial part of BGP especially when you have iBGP peerings. If a BGP neighbor cannot get to the Next Hop it will NEVER put the route into the routing table. While there is no automatic rule to this, generally when you have an eBGP…

Read More Read More

How did I miss this about BGP Backdoor???

How did I miss this about BGP Backdoor???

I have been working on my CCIE for over 2 years now and somehow I have never paid attention to the backdoor command. I would do an in depth overview of it but Steve did an excellent overview on his blog located here. Check it out! https://ccieblog.co.uk/bgp/bgp-backdoor TLDR I somehow never noticed that the network…

Read More Read More

IPv6 new book and First Hop Routing Protocols

IPv6 new book and First Hop Routing Protocols

I recently found out there is a newer IPv6 book that came out recently.  Most of the previous books I read were older version that still had the Site Local Addresses which has been depreciated. Here is a link to the book. http://www.ciscopress.com/store/ipv6-fundamentals-a-straightforward-approach-to-understanding-9781587144776   There are some gaps that are not covered in it but…

Read More Read More

Who doesn’t need a little PPPoE love in their day

Who doesn’t need a little PPPoE love in their day

In the following blog I will be configuring PPPoE with the constraints in the drawing.   R1 Configuration R1#config t Enter configuration commands, one per line. End with CNTL/Z. R1(config)#ip local pool TEMP 10.1.1.10 10.1.1.254 R1(config)#interface virtual-template 2 R1(config-if)#ip address 10.1.1.1 255.255.255.0 R1(config-if)#peer default ip address pool TEMP R1(config-if)#exit R1(config)#bba-group pppoe GROUP1 R1(config-bba-group)# *Oct 29…

Read More Read More

Integrated Routing and Bridging or IRB

Integrated Routing and Bridging or IRB

Concurrent Routing and Bridging (CRB) was the original form which allowed either Routing or Bridging on the same interface but not on both.   This has been since been replaced with Integrated Routing and Bridging (IRB).  IRB adds some additional features such as Routing and Bridging on the same interface. IRB uses a Bridged Virtual Interface…

Read More Read More

Where, oh where has the VLAN information gone? VTP and how it impacts the VLAN Database.

Where, oh where has the VLAN information gone? VTP and how it impacts the VLAN Database.

This is a topic we learn in the first few days of learning about Cisco.  However, in the normal day to day life we rarely have to think about this information. We usually do remember the vlan.dat file is stored in the nvram.  What we don’t remember is what kinds of impact the VTP version…

Read More Read More

Two great IPv6 Goodies

Two great IPv6 Goodies

If you are not familiar with IPv6 it works slightly differently then IPv4 when it comes to troubleshooting.  One of the issues I ran into is that I depend on ARP often when dealing with Layer 2/3 issues.  ARP as we know it in IPv4 doesn’t exist in IPv6.  Instead it uses a part of…

Read More Read More