GNS3 Images

Having used GNS3 a bit now I find some images are much more stable than others..

For others out there do any of you have any prefered IOS versions and sets that you use, or do other people not get the stability issues I seem to find.

I jsut spent ages setting up a VPN lab on two 7200's running the ios version 15.x.x. was all fine and then carried out a "WR" and dynamips bombs out and I lose my configs!

any ideas ?

Aaron

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Comments

stuh84

I haven't touched IOS 15 yet, as I think its a bit too new, and we dont run anything at work with it, and the exams aren't based on it yet either, so using anything higher than the 12.4T train hasn't made sense yet.

I stick to the 12.4T lot, usually between T(9) and T(17), mainly due to either being similar to work, or getting away from known bugs.

networker050184

I usually just use the IOS we are using at work. Currently its the 7200 12.2(33)SRC4 Advanced IP Services. If its stable enough for the production environment its good enough for a lab in my eyes.

DevilWAH

stuh84 wrote: »

I haven't touched IOS 15 yet, as I think its a bit too new, and we dont run anything at work with it, and the exams aren't based on it yet either, so using anything higher than the 12.4T train hasn't made sense yet.

I stick to the 12.4T lot, usually between T(9) and T(17), mainly due to either being similar to work, or getting away from known bugs.

Yer I jsut thought I would use the 15 ios to see what its like, not much different.

PS. jsut had a quick look at your blog, very nice!! And your wrong, you look exactly like all the other IT geeks I know

chmorin

I use a 3745 image, I find it has the most features for my uses (sometimes voice) and I have had no problems with crashes.

mikej412

I use Dynamips and Dynagen without any problems. No issues using 7200 15.0 Advanced IP Services IOS. I uncompressed my images before use.

I've taken my favorite (latest greatest Advanced Enterprise or Advanced IP Services) IOS images for each supported platform and configured them in GNS3. I've also taken some of my favorite multi-instance Dynagen .NET files and finally got those to load into the newer versions of GNS3 without issues -- but at that point I don't really gain anything running them with GNS3 (and lose some performance).

I'll pretty much stick with Dynagen for Cisco Router stuff and save GNS3 for Juniper or Firewall stuff (when I'm not using the real hardware).

DevilWAH

mikej412 wrote: »

I use Dynamips and Dynagen without any problems. No issues using 7200 15.0 Advanced IP Services IOS. I uncompressed my images before use.

I've taken my favorite (latest greatest Advanced Enterprise or Advanced IP Services) IOS images for each supported platform and configured them in GNS3. I've also taken some of my favorite multi-instance Dynagen .NET files and finally got those to load into the newer versions of GNS3 without issues -- but at that point I don't really gain anything running them with GNS3 (and lose some performance).

I'll pretty much stick with Dynagen for Cisco Router stuff and save GNS3 for Juniper or Firewall stuff (when I'm not using the real hardware).

Cool cheers at least its nice to know the 15 images should work.

I think I will look at Dynagen, I been putting it off for ages, as it meant learning the config files but I suppose I need to take the plunge!

I know there is loads of stuff out there to read, but if you have any quick links for Dynagen to get going I be greatful.

Cheers

Aaron

tiersten

IOS v15 will work so long as you're using one of the low end NPE emulations in Dynamips. The NPE-G1/G2 emulation is fairly buggy.

The 7200 platform was dropped from 15.1T so Dynamips is at a deadend for router support as all the implemented platforms are no longer supported past 15.0. 15.0 on a 7200 will be suitable for labs for a long time though.