Any solution to GNS3 (Dynamips) High CPU Usage

So I recently installed gns3 and i have one c1700 router ios image running. Whenever i run it, cpu usage goes to 90-100%. I tried doing idel pc value, but hasn't been much of help.

So any other permanent solution or should I just go back to packet tracer and forget gns3 as i don't want to cause issues with cpu.

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Comments

networker050184

You should be able to find a better idle pc value for sure. Just keep messing with it until you find the sweet spot. I was running 8+ router labs in Dynamips years ago on old 1g RAM lap tops. Anything modern should be more than enough horse power.

Skynet9

networker050184 wrote: »

You should be able to find a better idle pc value for sure. Just keep messing with it until you find the sweet spot. I was running 8+ router labs in Dynamips years ago on old 1g RAM lap tops. Anything modern should be more than enough horse power.

Do I have to find idle key for every ios image i add? Also it just once or every time i run the device?
Thanks!

kohr-ah

Yup you add it for every IOS image and you need to do it one time.

The newer GNS3 will do the idle PC calculations now before you even run the images the first time

DevilWAH

rad up on GNS3 the suggested images to use, there is a 3725 and 72xx image recommended that seem to be very stable.

I run 16+ 3725 routers on my 4gig laptop and CPU is between 5-10%

This to be carful off before you try to find the idel PC value.

1. let the image boot up fully,
2. log into the consol of the device and hit return and chose "no" to enter set up, then preform a copy run start. (i have seen issues when calculating an idle pc value when the devices is in its first boot. you may find one, then as soon as you start to configure the CPU shoots up.
3. only have one device in the topology and running when you want to find the idel PC value.

Then when you want to calculate the Idle pc value have task manage open along side it, go though each of the values and apply them in turn and see what the CPU vlaue changes to (look at each on for 10-15 seconds to see if there are any spikes)

Get the right image and the right PC value and you can have almost unlimited numbers running on a medium spec Laptop / PC