BGP Scalability Sample Nugget – Route Reflectors

October 3, 2018 at 10:39 pm

route reflectors

This Nugget is from my BGP – Scalability course at CBT Nuggets. This is one of 6 courses I created on BGP for you! Here we examine BGP Route Reflectors.


Pearson Education (InformIT)

Wrapped the Latest BGP Module at CBT Nuggets Today!

September 21, 2018 at 7:39 pm

BGP

That’s right- finished up the last Nugget today for the course below. I will post again here at the blog when the course appears on the CBT Nuggets website next week!

Border Gateway Protocol (BGP) – Scalability Mechanisms

  1. Module Introduction
  2. Private AS Numbers
  3. Peer Groups
  4. Session Templates
  5. Policy Templates
  6. IBGP Scalability Issues
  7. Route Reflectors
  8. Advanced Route Reflector Designs
  9. Confederations
  10. Configuring a Confederation
  11. Introduction to BGP Communities
  12. Community Attribute Formats
  13. Well-Known Communities
  14. Extended Communities
  15. Configuring BGP Communities

Remember, this is one more BGP module to complement the existing modules currently on CBT Nuggets:

  • BGP – Basic Operations
  • BGP – Peerings
  • BGP – Advertising NLRI
  • BGP – Cisco Routing Policy Mechanism

BGP Processes in the Cisco IOS

August 21, 2018 at 10:32 am

BGP

These are some notes that I used to help teach a recent module in my upcoming Border Gateway Protocol (BGP) – Cisco Routing Policy Mechanisms course at CBT Nuggets. Enjoy!

There are many processes that work together to provide BGP services in the Cisco IOS. To see those that are running on your IOS version (and hardware), run the following command:

show processes cpu | include BGP

There are four core processes you should definitely see:

  • I/O – this process is responsible for moving prefixes in and out of the appropriate InQ and OutQ mechanisms; this allows us to both send and receive prefix information
  • Router – this process is the workhorse of the BGP system and takes care of policy application and the BGP Best Path Decision Algorithm
  • Scanner – the scanner process defaults to one minute intervals of operation; you can change this with the bgp scan-time command under the BGP configuration; this process is scanning for changes that might require a revamp of the BGP information (an example would be a prefix removal due to next hop reachability issues)
  • Scheduler – this process is responsible for scheduling the various BGP processes that might be running

To see the Scanner process in action – you can use the command – debug ip bgp events

Remember, you might see other BGP related processes running on your system. Cisco is constantly working hard on their implementation to improve efficiency and reduce CPU workloads. For example, you might see:

  • BMP Server – this service permits the functionality of BGP Monitoring Protocol for neighborships
  • Event – this service helps the Scanner with its potential workload – it quickly responds to events like network statement introduction and redistribution commands
  • NHT – a next hop tracker process that, again, assists the Scanner service with its work
  • Open – you might get lucky and catch a glimpse of this process – it exists to assist with neighbor formation