GNS3 - System Requirements??

I've noticed GNS3 mentioned a fair bit on here but up till now I've dismissed it in favour of real hardware.

I'm thinking of at least having a look at it - if my pc specs are ok. I've got a 2.4GHZ Dell with 768Mb RAM. I don't want to upgrade it as it's only used for web browsing and a bit of work from home stuff.

Will this run GNS3 ok? I wouldn't want to be restricted too much in terms of the topologies/labs I could create.

Or would I be best to stick to actual hardware routers?

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Comments

tiersten

GNS3 = GUI for Dynamips. You don't have very much RAM and that will be the limiting factor here. Go try it out and find out how many you can run...

captobvious

BadBoy House wrote: »

I've noticed GNS3 mentioned a fair bit on here but up till now I've dismissed it in favour of real hardware.

I'm thinking of at least having a look at it - if my pc specs are ok. I've got a 2.4GHZ Dell with 768Mb RAM. I don't want to upgrade it as it's only used for web browsing and a bit of work from home stuff.

Will this run GNS3 ok? I wouldn't want to be restricted too much in terms of the topologies/labs I could create.

Or would I be best to stick to actual hardware routers?

I'd throw in the max RAM your system will take.

I wasn't into GNS3 when I first started studying. The more I got into fiddling around with it, I wish I would have gone this direction especially for the CCNA track. Could have saved mucho dinero but then again I have a good start on a decent home lab!

As far as limiting yourself, that would depend on how much your system can take!

BadBoy House

i'm gonna stick with physical hardware - i've got some already and nothing beats real hardware in my opinion.

blackninja

BadBoy House wrote: »

i'm gonna stick with physical hardware - i've got some already and nothing beats real hardware in my opinion.

That's what I thought until I came across two programs that literaly changed everything for me:

Vmware workstation & GNS3

I use loads less electric, I havn't got the sockets in my lab room nearly overloading and my room is cool.
This time last year I had two fans cooling the room (more electric). And the best part - quiet, O I love the quiet.

I can now run labs at midnight and not have the wife knocking at the door.

I still use my physical lab at times, but not much. I think I only keep it as it looks cool

captobvious

blackninja wrote: »

That's what I thought until I came across two programs that literaly changed everything for me:

Vmware workstation & GNS3

I use loads less electric, I havn't got the sockets in my lab room nearly overloading and my room is cool.
This time last year I had two fans cooling the room (more electric). And the best part - quiet, O I love the quiet.

I can now run labs at midnight and not have the wife knocking at the door.

I still use my physical lab at times, but not much. I think I only keep it as it looks cool

+1 on the less power used!

Plus you get experience with VMware, brilliant!

beach5563

Well since I dont have a powerful computer to run GNS3 I may as well get a real lab because it costs to get a computer to handle it. A friend of mine used 3 1720 routers and 2 2950 switches for ccent and ccna and spent under $200. I love the idea of GNS3 though.

Roguetadhg

It doesn't take a high-end computer to run it. By the way, nice thread revival :P

astrogeek

beach5563 wrote: »

Well since I dont have a powerful computer to run GNS3 I may as well get a real lab because it costs to get a computer to handle it. A friend of mine used 3 1720 routers and 2 2950 switches for ccent and ccna and spent under $200. I love the idea of GNS3 though.

I don't know what kind of PC you think you need, but GNS3 runs perfectly fine on most modern PC's/laptops, (even modern for the time this thread was started lol). You don't need that much processing power to run it, especially if you're just doing CCNA material which usually only requires 3 or 4 routers. Don't discount Cisco's Packet Tracer either, I still prefer GNS3, but Packet Tracer is a great beginner's tool to get started on.

Even if you want to start building a lab you can still incorporate GNS3 as I have. I bought a Dell 2850 from e-bay for $300 along with 3 quad nic cards (about $30-50 each), and can run GNS3 from this server connected to my four 3550 switches. My lab is based on a CCIE lab, which is more than I really need for right now, but it's worth mentioning what is possible because I now never use the two 2600XM routers I bought when I first started building my lab. I just added some pics in my profile album if you want to see what my home lab looks like - but I still use GNS3 on my work laptop quite frequently as well, and my work laptop is pretty basic in terms of performance.

You don't actually need a server like what I did, I only mention it because $300 was cheaper than if I built a new PC from scratch which is the main reason I went that route - otherwise I'd still be using an old PC had its motherboard not died on me

Roguetadhg

That's the good thing about GNS3. The fact you can build large router topologies cheaply. I haven't experimented with using a computer as a router. But hearing you can subsitute routing with one GNS3 means you can focus on buying the switches you need.

But I question this for Voice and Security. I admit, I haven't spent too much time to look at the topologies and needs. I suspect the amount of money I'd save would be lower going into the concentration tracks as they're not emulated and [probably] not as worried about the routing aspects.

beach5563

astrogeek wrote: »

I don't know what kind of PC you think you need, but GNS3 runs perfectly fine on most modern PC's/laptops, (even modern for the time this thread was started lol). You don't need that much processing power to run it, especially if you're just doing CCNA material which usually only requires 3 or 4 routers. Don't discount Cisco's Packet Tracer either, I still prefer GNS3, but Packet Tracer is a great beginner's tool to get started on.

Even if you want to start building a lab you can still incorporate GNS3 as I have. I bought a Dell 2850 from e-bay for $300 along with 3 quad nic cards (about $30-50 each), and can run GNS3 from this server connected to my four 3550 switches. My lab is based on a CCIE lab, which is more than I really need for right now, but it's worth mentioning what is possible because I now never use the two 2600XM routers I bought when I first started building my lab. I just added some pics in my profile album if you want to see what my home lab looks like - but I still use GNS3 on my work laptop quite frequently as well, and my work laptop is pretty basic in terms of performance.

You don't actually need a server like what I did, I only mention it because $300 was cheaper than if I built a new PC from scratch which is the main reason I went that route - otherwise I'd still be using an old PC had its motherboard not died on me

Yea that sounds good man. I have an HP Elite book, its a core 2 duo and has 2 gigs of ram in it. I just got it from a friend of mine. I always hear you need an i5 processor and about 6 gigs of ram.

fsanyee

beach5563 wrote: »

Yea that sounds good man. I have an HP Elite book, its a core 2 duo and has 2 gigs of ram in it. I just got it from a friend of mine. I always hear you need an i5 processor and about 6 gigs of ram.

That processor is much better than mine, and I can run more than 10 router on GNS3. You may need some ram...

beach5563

fsanyee wrote: »

That processor is much better than mine, and I can run more than 10 router on GNS3. You may need some ram...

ok I think it maxes out at 3 gigs I think, I will have to check on it. If I do get it to work I guess I can just buy one router like a 1720 and maybe use packet tracer for switching?

Roguetadhg

I used pack tracer for switching when I got desperate. I hated it.

beach5563

Roguetadhg wrote: »

I used pack tracer for switching when I got desperate. I hated it.

yea I know what you mean, I may try to get two 2950 switches and try to get a router. I have seen a lot of people have success with it for switching.

beach5563

fsanyee wrote: »

That processor is much better than mine, and I can run more than 10 router on GNS3. You may need some ram...

Also I just found out that I can upgrade my ram to 8 gigs. Its running windows 7 ultimate. This sounds like it should be good enough for CCNA stuff.

NetworkVeteran

beach5563 wrote: »

Also I just found out that I can upgrade my ram to 8 gigs. Its running windows 7 ultimate. This sounds like it should be good enough for CCNA stuff.

What you have (2GB) is probably already enough for Dynamips for even CCNP. For example, one of my systems has 2 GB of RAM and it can run a 6-device Dynamips CCNP topology--no delays, no slowdowns. Specifically, with dual stacks and two routing protocols running on a converged topology, it consumes 130MB of RAM, although it's permitted to use upto 793MB of RAM.

If you're excited to buy real routers or more memory for your PC that's fine, but it's certainly not necessary to master the exam content. At the CCIE level, I could see memory upgrades being essential for success with Dynamips.

beach5563

NetworkVeteran wrote: »

What you have (2GB) is already enough for Dynamips for even CCNP. For example, one of my systems has 2 GB of RAM and it can run a 6-device Dynamips CCNP topology--no delays, no slowdowns. Specifically, with dual stacks and two routing protocols running on a converged topology, it consumes 130MB of RAM, although it's permitted to use upto 793MB of RAM.

Oh yea I forgot about Dynamips, I heard its actually GNS3 without the GUI interface if Im not mistaken. I will try to download it and get an ios from somewhere or at least get maybe a 1720 router and get the ios off that maybe. Just need to figure out the switching stuff. A friend of mine told me a few years ago he did his CCNA all the way through CCNP with Dynamips.

NetworkVeteran

Oh yea I forgot about Dynamips

I like the GNS interface to access Dynamips. (I did it without, before GNS, but it was more work setting up the topologies.)

I know someone who achieved his CCIE using GNS plus Dynamips.

beach5563

NetworkVeteran wrote: »

I like the GNS interface to access Dynamips. (I did it without, before GNS, but it was more work setting up the topologies.)

I know someone who achieved his CCIE using GNS plus Dynamips.

Yea Ive worked around some guys that have used GNS3 and Dynamips too. They worked with routers a lot on their jobs anyway so at home they could really create some humongous labs with GNS3. So you think if I juice my ram up to maybe 4 gigs that would be enough for GNS3 or just roll with Dynamips, man Im so anxious to do the GNS3 setup. : )

NetworkVeteran

beach5563 wrote: »

Yea Ive worked around some guys that have used GNS3 and Dynamips too. They worked with routers a lot on their jobs anyway so at home they could really create some humongous labs with GNS3. So you think if I juice my ram up to maybe 4 gigs that would be enough for GNS3 or just roll with Dynamips, man Im so anxious to do the GNS3 setup. : )

When I said my 2GB system was sufficient to run Dynamips with 6 devices, I really meant GNS + Dynamips with 6 devices. I'd just go with GNS, set your IDLEPC values per the instructions, and you'll see right away if you can run enough devices for your labs.

beach5563

NetworkVeteran wrote: »

When I said my 2GB system was sufficient to run Dynamips with 6 devices, I really meant GNS + Dynamips with 6 devices. I'd just go with GNS, set your IDLEPC values per the instructions, and you'll see right away if you can run enough devices for your labs.

Yea thats what I was thinking. I have a video bookmarked with Jeremy Ciora from CBT nuggets explaining how to download and setup GNS3. After getting all this info from you I realize I should have enough to do the GNS3. What type of router should I purchase for the IOS and all? Thanks so much for your help. I have a telecommunications background and some Data Center/Tech Support skills. I like Voice and may go that route after CCNA maybe. Should I get a router that would work for CCNA voice? Just wondering.

NetworkVeteran

What type of router should I purchase for the IOS and all?

Ideally, you might want a recent IOS for a model that supports both Ethernet and Serial interfaces and that GNS supports, for example a c3725. I can't offer specific recommendations for individual purchase. I usually have access to many version of IOS via an employer. There are rumors that some folks who do not have access to IOS images via employers find more shady ways to secure an image for training without buying one. I, of course, do not condone any such actions. I have no experience with CCNA Voice.

beach5563

NetworkVeteran wrote: »

Ideally, you want a recent IOS for a model that supports both Ethernet and Serial interfaces and that GNS supports, for example a c3725. I can't offer specific recommendations for individual purchase. I usually have many options via an employer.

Ok I understand, thanks so much. I will focus on getting GNS3 downloaded first and then go from there. I may just go with GNS3 for routing and packet tracer for switching if I can get any switches. Just depends on the finances.

astrogeek

If you're pressed for money don't buy anything, your laptop is just fine to run GNS3, I wouldn't even bother upgrading the ram because you aren't likely to max it out anyway. GNS3/dynamips uses more processing than RAM. I also just want to clarify that Dynamips is bundled with GNS3, some people get confused when people talk as if these are separate programs. All you need to do is go to www.gns3.net and click the big download button on the right. After that, follow the instructions from the same website or Jeremy's equally helpful instructions to add an IOS image and you're good to go. There is a little bit of a learning curve, but that's what forums are for

Check your PM box too

beach5563

ok thanks so much, I just downloaded GNS3. I love all the goodies that go with it. I will watch Jeremys video and try to get the IOS stuff set up today.

beach5563

So far so good as far as getting this downloaded today. I'm going to work on getting an ios next. Thanks again guys.

beach5563

One more question. Looks like I will need to get a router so that I can copy the ios over to GNS3. I want to get a 3600 series router because it looks like I can maybe use it for some switching stuff in GNS3 according to info I saw online. Is there a certain model I need for that? I have seen some with the 12.4 ios. I mean I ccould duplicate it a few times in GNS3 and also use it for some basic switching too maybe. I saw some on ebay and ciscokits.com too.

JockVSJock

Roguetadhg wrote: »

I used pack tracer for switching when I got desperate. I hated it.

I agree, Packet Tracker is pathetic. I hate the limitations of IOS commands.

I'm in the process of converting over to GNS3 as I type this up.