- In this module, I'd like to talk a little bit
about Cisco platform considerations.
Now, what do I mean by that?
I'm assuming that you're a first time user of GNS3
and as such, you need to be aware
that in order to use this application, this software,
at minimum, you're gonna need
to download two pieces of software.
You're gonna have to download the GNS3 software itself,
which actually comes bundled
with a whole bunch of other stuff, which is kind of neat.
And then you're also gonna have to download
at least one Cisco IOS software image,
possibly more, depending on what you need to do.
So the order that you do that in is really up to you.
Doesn't matter to me whether you download
the GNS3 software first or the Cisco IOS.
But I'm just gonna start with the assumption
that the first thing on your mind
is which Cisco IOS software image is appropriate
for what I wanna do with GNS3.
So let's talk a little bit about that.
Because GNS3's main job is to emulate Cisco hardware,
in other words, you're using real Cisco IOS software
within the GNS3 application, but you don't have a chassis,
you don't have anything physical that you can feel and touch
and yet that software needs to believe
that it's running within a real Cisco router,
and that's the real power of GNS3,
that's exactly what it does.
It creates these virtual routers running real software.
But because of that, if you know anything about Cisco,
you know that Cisco has hundreds and hundreds
of makes and models of routers and switches
and there's no way that GNS3 could emulate all of them.
So for that reason, GNS3 only emulates or simulates
certain router platforms.
So you need to know that
because there would be nothing more frustrating
than if you went through all the process
of getting ahold of and downloading a Cisco IOS image
and one of three things happening.
Either the IOS image you downloaded is not supported
by GNS3 at all, and then you'd have to contend
with all the error messages and things that you're seeing,
or possibly, it is supported by GNS3,
but it's buggy, it has all sorts of problems
and maybe leads to all sorts of errors,
or the third scenario is the software you download
runs just great within GNS3,
but because it's not the platform that you really needed,
it doesn't support the features that you want.
For example, what if you're doing a lab on ATM,
asynchronous transfer mode,
and you download software for a router
that doesn't support ATM,
it doesn't even have, in the real world,
any modules or adapters or interfaces that support ATM.
Well now your GNS3 supports that software
but you can't configure ATM
because the software you selected doesn't run that feature.
So, let's just focus for the moment in this video
on how do we figure out what Cisco IOS software
is supported by the GNS3 platform
and works the best on that.
So to do that,
I'd recommend that you go to the GNS3 website,
as you can see right here, gns3.com.
And if you haven't already done so,
make sure that you go to the sign up button right here
and you're gonna want to create a username and password,
basically register on their website.
So once you click on that,
you'll just type in your email address
and then whatever password you want,
and then at that point, you'll have the ability
to download the software and participate in the community
if you ever have any questions
or if you just wanna look up some of the questions
that other people have asked.
So let's go ahead and do that, let's log in.
And depending on your network speed and everything else,
it might take a certain amount of time.
So now we're logged in.
Here it comes, coming back up.
Great, okay, so at this point, once you're logged in,
now remember, the question we're trying to ask is
what Cisco IOS software images are supported by GNS3.
So to answer that question, we're gonna wanna go right here
and click on where it says support.
So go ahead and click on support.
And then from here, we're gonna go to documentation.
Now there's multiple ways to get this question answered,
this is just one way that I've discovered.
So once we click on documentation,
so here within the getting started section,
what we wanna look at is adding IOS images,
that's where we're gonna go to.
Click on that link.
Now this whole document, if you read through it,
is actually about,
once you have your Cisco IOS software image,
how do you get it loaded into GNS3,
how do you get GNS3 to recognize it
so it can create a virtual router out of that software.
But we're not even at that point yet.
Right now, we just have to figure out
what software is compatible with GNS3.
So to answer that question,
right here in this sentence, right there,
it says Cisco IOS image listed in this document,
that is actually a link.
So if you go ahead and click on the words there,
in this document, that will take you to another document
that actually displays the various Cisco IOS images
that are supported by GNS3.
You can see here it supports the 1700 series images,
the 2600 series, 3620's, on and on and on
all the way down to, at the very bottom here,
is the 7200 series.
Couple of things to point out about this.
Now number one, as I do this recording,
it's currently mid-February of 2016, so keep that in mind.
So as of right now, when I'm doing this recording,
if you wanna practice features
that are only found in the 15 train,
like 15.1M or something of IOS,
the only software currently that GNS3 supports for that
is the 7200 series.
Okay, so if you select any of the other platforms,
you'll have to use 12.3, or 12.4, or something like that.
Now, if you are preparing for your CCNA or even your CCNP,
chances are you won't necessarily need
some of the newer bells and whistles
that are in the 15 train of Cisco IOS.
12.4 should be more than sufficient for you
for whatever you need to do.
So you can choose from any of these platforms right here,
and those should get you working.
Now, let's say that you're pursuing your Cisco CCNA,
and you're watching this video, you're saying
"But Keith, I don't know anything
"about the differences between Cisco routers.
"You know, I've got a login for Cisco,
"I can get ahold of Cisco IOS images
"for pretty much any router, but which one should I choose,
"you know there's about seven or eight routers
"in this list here, which one should I pick,
"since I don't really know the differences
"between one router and another?"
What I would recommend in that particular case,
if we go up here, I would suggest
that you get ahold of software images
that support either the 3725 series of router,
or the 3745 series of router.
If you can get ahold of those, those would be the best.
Why is that, well, a little bit later in this video series,
I'm gonna talk about switching in the world of GNS3
and how you accomplish switching.
And if you get a software image
for one of these 3700 series of routers,
that comes along with it, a switching module.
Nothing else you have to download, nothing you have to do.
But basically, you can turn on a switch
that operates within, or inside, of that router,
and now you can do switching and routing.
Most of the other platforms
don't support that switching module.
So if you don't know anything about Cisco routers at all
and you're just looking for advice
on which particular one to choose for your IOS image,
I would select a 3725 or a 3745 image.
So with that, we'll conclude this particular video
and in the next one or two videos after this,
I'll just show you one or two other things
you wanna think about about selecting a Cisco IOS image.
In other words, we'll look at memory considerations,
you know, how much memory does each software image use,
because it's gonna use memory in your laptop
when you run GNS3.
And secondly, we wanna think about, well,
various different software images
support different features.
There's Cisco's IP services, which is different
than Cisco's advanced enterprise feature sets.
And you wanna make sure
that when you're downloading software,
it runs the features that you need for your topology.
We'll talk about that in the next upcoming videos.