GNS3 Linux version better than Windows?

Does anyone have any experience with GNS3 and can comment on whether the Linux version is more stable than the Windows? GNS3 keeps crashing because of a Dynamips error, and I have also been experience odd errors that don't make much sense to me.

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Nate--IRL--

I'm actually using the windows version of GNS3 with WINE on Linux. I couldn't get the Linux version to work

Nate

networker050184

I've used both and haven't seen much difference as far as stability goes.

veritas_libertas

Well at least my story isn't that different

fsanyee

I dont see too much defference either. It's harder to make the linux version to work.

it can help a lot if you try another IOS.

veritas_libertas

I'm having a problem where after I add a third router the CPU spikes to 75% from 15/18% and then Dynamips crashes. Very annoying since I have to go through and re-configure everything. Then again, it has helped me memorize several commands

ChickenNuggetz

veritas_libertas wrote: »

I'm having a problem where after I add a third router the CPU spikes to 75% from 15/18% and then Dynamips crashes. Very annoying since I have to go through and re-configure everything. Then again, it has helped me memorize several commands

Wow that's a big spike. Have you configured the idle PC values for each IOS image you're using?

veritas_libertas

ChickenNuggetz wrote: »

Wow that's a big spike. Have you configured the idle PC values for each IOS image you're using?

Yes.

Do you have to do this for every router you add?

QHalo

Every router needs an idlepc value.

fsanyee

You have to do this with every different IOS image, not every router.

QHalo

I always put it under the actual router itself. Worked just fine. Guess you can do it either way. You should also look into idlemax values as well.

GNS3 • View topic - Investigating Idlepc idlemax to minimise CPU usage

veritas_libertas

QHalo wrote: »

I always put it under the actual router itself. Worked just fine. Guess you can do it either way. You should also look into idlemax values as well.

GNS3 • View topic - Investigating Idlepc idlemax to minimise CPU usage

Thanks.

I'll have to play around with it more. I'm going to have to get my home lab running smoothly, because I have a feeling I'm going to need to rely on it more than GNS3.

QHalo

I'm not a huge fan of GNS3 to begin with. I'm sure it works great for people but Dynamips/Dynagen by itself works just fine on Linux. I used it for my CCNA Security exam on Ubuntu and had no problems at all. If you like looking at the actual topology on screen you might find it difficult at first, but if your topology doesn't change that often it's not that big of a deal to just create a small Visio of it and look at that instead. Less resources too which means more routers can run. Plus I think it makes it a bit more real world in that you're not going to be able to see link lights of the routers you're configuring so why start relying on that?

Go back and look at the dynamips wiki, fsanyee is right about just putting it under the main router definition. I apparently made it harder than it needed to be but the end result was the same.

carwashguy

My desktop is old so GNS3 does run slow, but far better with linux now than when it was windows.

veritas_libertas

QHalo wrote: »

I'm not a huge fan of GNS3 to begin with. I'm sure it works great for people but Dynamips/Dynagen by itself works just fine on Linux. I used it for my CCNA Security exam on Ubuntu and had no problems at all. If you like looking at the actual topology on screen you might find it difficult at first, but if your topology doesn't change that often it's not that big of a deal to just create a small Visio of it and look at that instead. Less resources too which means more routers can run. Plus I think it makes it a bit more real world in that you're not going to be able to see link lights of the routers you're configuring so why start relying on that?

Go back and look at the dynamips wiki, fsanyee is right about just putting it under the main router definition. I apparently made it harder than it needed to be but the end result was the same.

I actually didn't even realize that was possible. Nice.

bermovick

Not sure if this is applicable, but for some reason if I try to use 2 different router models (or I guess possibly 1 model with 2 different IOSs) at once, I can never really get a stable run going. I've never had it crash, but the cpu usage is higher than it reasonably should be (based on the cpu usage of each separately). Easy solution of only using 1 model/ios type per lab and I don't see that ever being a problem.

Otherwise the only real difference I've had between running it under linux and windows is the usual bonuses of linux - the better use of resources means less impact per router added so you could get larger topologies built with the same processor/ram (my record in linux was 11 routers under linux when I had 2G ram. Under windows I could only get 5-6 typically)

Heero

Linux versions of dynamips don't have a 2gb memory limitation so you don't have to run several processes when doing larger topologies. I will say that I have never used gns3 or any other GUI for dynamips. Good old console based management of the topology works fine for me.

QHalo

bermovick wrote: »

Not sure if this is applicable, but for some reason if I try to use 2 different router models (or I guess possibly 1 model with 2 different IOSs) at once, I can never really get a stable run going. I've never had it crash, but the cpu usage is higher than it reasonably should be (based on the cpu usage of each separately). Easy solution of only using 1 model/ios type per lab and I don't see that ever being a problem.

Otherwise the only real difference I've had between running it under linux and windows is the usual bonuses of linux - the better use of resources means less impact per router added so you could get larger topologies built with the same processor/ram (my record in linux was 11 routers under linux when I had 2G ram. Under windows I could only get 5-6 typically)

Yeah linux is much better. I would use 7200s or 3725s. Those support all the 12.4-15 feature sets just fine. 3725s are what I used as they also had SDM support for the CCNA:S.

Nate--IRL--

QHalo wrote: »

I always put it under the actual router itself. Worked just fine. Guess you can do it either way. You should also look into idlemax values as well.

GNS3 • View topic - Investigating Idlepc idlemax to minimise CPU usage

Thanks for that - it really is an invaluable tip, it makes larger topologies much easier on my ageing laptop.

Nate

CodeBlox

ChickenNuggetz wrote: »

Wow that's a big spike. Have you configured the idle PC values for each IOS image you're using?

I configured IDLE PC values and the changes don't stick for one of my IOS images after restarting the routers

Works on another of them just fine though.