VLANs/ Subnets help

[Ste_Harve]

Hi all,

I'm looking at the advantages of using VLANS and subnertting parts of our network. Basic network is 1 seperate admin network linked to curriculm network with a seperate nic in the admin server and trusts set up.

Our curriculm network is spread across 4 seperate buildings all linked with fibre. I've been told that if i was to use subnets it would make things quicker. I've never looked into subnetting but am interested in it now. Could someone please give some examples of how it would be done?

I'd also like to have the admin and curric on one physical network so that I can access sims from anywhere in school. Could this be done with vlans? and if so would someone be able to give an example?

Cheers,

EDIT - I'm also wanting to implement a thin client solution but want to be able to boot these from the network, without having to press a key to boot, while still being able to use WDS. Is there a way round this?

[beast_gts]

From the sound of it you either want to split your network into five subnets or two subnets and break one up into four sub-subnets. Either way you'll need some routing somewhere...

Does each building have its own sever?

[Ste_Harve]

All the servers are located in one room, my office. In here there connected to a HP ProCurve 2824. All the switches on the other ends of the fibre are managed and most are HP 2626 or 2650.

Can anyone give a layout pic of their current networks and i'll see if mine can be compared.

[andyrite]

I've just vlan/subnetted my network off. Took a while but worth it.

I assume the fibres go into the 2824? How many machines do you have on each physical segment? How are you going to join the networks together?
Have you got dhcp running?

The 2824 should do the routing for you. So you should be ok there.

I'm not sure if it will make things any quicker. It depends on how many devices you are running.

[j17sparky]

How many nodes is there?

I doubt they'd be any advantage to it tbh. We just have the admin on the same subnet but in their own scope with static ips.

[Ric_]

@Ste_Harve: I cannot really see the point of adding the subnet complexity into your situation. The links between buildings will be as fast as those within buildings anyway. You would only really see a benefit if these links were smaller and you had hardware within the buildings that had to talk to each other. VLANs are useful and can help you set up CoS and Qos mind.

As an aside, I have a very similar set up but with 7 buildings on one site. I also have thin clients. You might find it useful to come for a gander - I'm less than half an hour away

[Ste_Harve]

Right thanks for the words of wisdom. I'll try to answer as many questions as possible.

We have about 250-275 nodes in total, of which about 200 are run of the fibres. This are divided up between the buildings as such.

A = 35
B = 20 (5 of which are IWB's)
C = 40 (2 of which are IWB's)
D = 97 (32 wireless laptops, 10 IWB's)

All the other nodes are cat 5 into switches in the server room linked at 1gb. We have DHCP running.
Don't know about joining the networks together. Do you mean admin and curic or the seperate subnets? If it's curric and admin, we can link there main switch into our curric network as it shares a data cab.

@j17sparky - How do you mean on the same subnet? Do you use reserved ips in DHCP to achieve this in their scope and does it work well? Were running parsql and need to get some speed here as taking 35 registers at one time slows thiongs down.

@Ric_ - I think it would be useful to have a gander. I'll send you a PM. Can you still use RIS/WDS without having to do anything special on the thin client side to get them to boot automatically?

Thanks guys.

[ICTNUT]

Hi Guys,

Sorry to Hijack this thread but this is not 100 miles off what I am trying to do.

I have VLANS in place already at the school (3 of them) and I am thinking about adding a 4th for the thin Client setup I am rolling out over the summer.

My question is this: If I setup a dhcp scope just for the ThinClients how do I ensure that the ThinClients are the only ones to get the IPs from this scope along with the settings required for PXE booting and to ensure that RIS is not affected (as it currently is at the moment).

Lost at sea here, monday morning, flooded, drowning, help!.....

{edit}
our current setup is as follows (inherited):

IP Range: 192.168.49.x -> 192.168.52.x
Subnet: 255.255.0.0

I want to move to a subnet of 255.255.248.0 and I am in the planning stages of this.

{/edit}

[Geoff]

You need one scope per network segment (in this case that means per VLAN).

[NetworkGeezer]

And all IPs allocated from reservations otherwise scope placment would be allocated at random if the DHCP server straddles both VLANS.

[Geoff]

It's a shame that when using Windows DHCP you can't put clients in scopes based on vendor class or network interface, like you can with ISC DHCP.

[ICTNUT]

The DHCP server does straddle all the VLANS.

So if i understand coorectly I would need to do the following:

VALN 1 - (Default) - Assigned to infrastructure i.e. servers, switches etc. (ALL DHCP Reserved)

VLAN 2 - ADMIN - Assigneed to NON student PC's i.e. SIMS PC's - Currently DHCP but these would change to DHCP reserved

VLAN 3 - CURRIC - Assigned to all students PC's - Currently DHCP and these could remain as such

VLAN 4 - THINC - Assigned to ThinClients (Not yet in place) - These would be DHCP Reserved.

Within DHCP simply create the 4 scopes relating to the above...

I my mind working as it should on this..?

It's a shame that when using Windows DHCP you can't put clients in scopes based on vendor class or network interface, like you can with ISC DHCP.

Maybe one day when Cisco rules the world it may become the standard of all things but until then ..........

[andyrite]

What switches you using?

[ICTNUT]

@ Andyrite: A mixture but all layer2 managed. I am trying to standardise the switches based on NetGear (GSM7224/7248) as these are really nice and support fibre but not there yet.

[andyrite]

I've got more of a geographical vlan setup. I have a default vlan which is just for the switches. A server vlan and the rest are geographical areas.

Each vlan has it's own ip address in different scopes. IP helper is set to the dhcp server ip on each vlan, so depending where you are in the building you get a different ip address.