Noob Question

[e.beaudoin]

Hey there, I am quite new to this whole networking scene. any help would be greatly appreciated, And do do expect to hear the "look at the basic CCNA".

But let me try to ask anyways, in hopes some one can shed some light on this.

So, as I said I am very new to all this, my co worker had asigned me a task that exceeds my capabilities at the moment.

I will only present one problem here.

I was told to make a network consisting of 7 departments in the inside network.

Each department is connected to two switches, which in turn are connected to another two switches that connect to two routers.

I want to be able to seperate all these networks by subnets, but I am unsure as to how I can do this. The two routers have 3 interfaces in the inside.

One going to switch A, another to Switch B and another to the other router. Each interface needs to have it's own unique gateway on it's own seperate subnet (From what I understand). And When I am implimenting a default gateway on a computer it has to be to on the same subnet as the router interface. How would I be able to make all of these fault tolerant paths a gate way for each pc? I need to have about 300 computers per network. I figured I can not subnet because I wont be able to get them to access any gateway that isnt on their subnet. I was going to use vlans, but I am still confused as to what I put as the default gateway.

Any one have maybe a tutorial on this i can follow?

[vmiller]

1. What model of switches are installed at the department level ?  what version of operating system ?

2. What model of switches are hanging off the routers ? what version of the operating system ?

3. What routers are in use ?

You need to get read access to the configurations of these devices.

A lot of what can and cant be done is dependent on the features available on the platforms. so

here is some light reading, its a bit of overkill but the model is pretty much the same. It will give you a frame work.

http://www.cisco.com/en/US/docs/solutions/Enterprise/Campus/HA_campus_DG/hacampusdg.pdf

[Edison Ortiz]

You can draw your typical building block (access, distribution/core and wan layers).

At the access layer, you will build your Vlans. Each switch pair to each department will have the L2 and L3 information.

You mentioned 300 hosts per subnet so it means you need /23 defined in the L3 interfaces. The default gateway will be configured on each switch pair with HSRP.

For instance, on switch A from the pair switch:

vlan 20

name engineering

interface vlan 20

ip add 192.168.1.2 255.255.254.0

standby 20 ip 192.168.1.1

standby 20 priority 150

standby 20 preempt

then on switch B from the pair switch:

vlan 20

name engineering

interface vlan 20

ip add 192.168.1.3 255.255.254.0

standby 20 ip 192.168.1.1

standby 20 preempt

On the workstations, you will configure 192.168.1.1 to be the default gateway. You may also need to configure 'ip helper-address' under the vlan 20 interfaces for DHCP but that's an added design option.

On these switches, you will need to advertise all your subnets towards the core/distribution block via a dynamic routing protocol such as OSPF or EIGRP.

This should give you a basic foundation of what needs to be done but I highly suggest to get any CCNP/A level book on design and get back to the basis.