Sunday, October 26, 2008

Study Update

I am quite content running labs on Dynamips until I purchase all the equipments in Jan. So far, I have completed reading CCIE R&S certification guide. At present, I am reading Routing TCP/IP Vol 1. I can safely say the more you read and try out labs, its like joining pieces of a large puzzle. You can make co-relations between different entities and couple of what if scenarios start appearing. Ofcourse, I have to switch back and forth between books to quickly brush some fundamentals and then continue reading for things to make sense at times.
It's quite hard dedicating your weekends, etc towards your study. Well, I am certain it will be worth the effort in the end. When I've finished reading Routing TCP/IP Vol 1, I should be able to post some interesting things across my study so far.

Wednesday, October 1, 2008

Dynamips Reduced Processor Utilisation

I am extremely elated to share the good news on my Dynamips test, i.e Internetwork Expert Toplogy . I have got my CPU usage close to 38% - 46%. I had earlier reported my disappointment in not being able to reduce processor utilization below 70%- 80%
And here comes the tip of the day to reduce CPU usage.

Below are System Specs

  • OS :Ubuntu 8.04 64 Bit
  • Processor : Intel Core 2 Duo Processor T9400
  • IOS image : c3640-jk9o3s-mz.124-10c.bin
Steps to Reduce CPU utilisation
  • Calculate your idlepc using method detailed in the Dynamips/ Dynagen tutorial (Calcuating idlepc values)
  • Start all devices {start /all}
  • Make sure you telnet to all devices and leave it at the router prompt, even if your not using the device. Once all devices have their router prompts you'll see the cpu usage drastically reducing.
I observed during my tests that simply starting all devices would still leave your processor utilisation high. However, telnetting to all devices and leaving them at the router prompt dramatically reduced processor utilization.