HP VLAN Setup 2910Al

[jwc1972]

Hello

I Have Two Hp Switches 2910Ag. One switch in the office and another switch in the warehouse. The buildings are connected by Fibre
We are running windows server 2003 DC giving out Ip address of 192.168.1.*
Switch Office
Vlan1
Untagged 1-40
Tagged 48

Vlan 100
unatgged 41-47
tagged 48

I have the same setup for the warehouse switch. The question is I would like vlan1 to give out ip address of 192.168.1.* and the Vlan 100 to give out address 10.20.10.* Is this possiable? So when i connect a cable into port 42 it gives the client ip address 10.20.10.* is that correct?

[Mohammed Faiz · Accepted solution]

Hi,

Yes that is possible. You need to configure routing on one of your switches ("ip routing") and give it an IP address on both VLANs.
You can the configure an IP helper address on VLAN 100 to point to your DHCP server ("vlan 100 ip helper-address 192.168.1.x").
Then configure the new scope on your DHCP server.
Note that this setup will allow VLAN 1 clients to communicate with VLAN 100 clients (as the switch will route between the VLANs)

[jwc1972]

Cheers

I setup the Switch Office ip address is 192.168.1.220
Warehouse switch ip address is 192.168.1.221

What is ip address helper? is that the domain controller? How would i add ip routing in the config?

Switch Office

Vlan1
ip routing ?
ip address 192.168.1.* 255.255.255.0 ???
ip address helper ?
Untagged 1-40
Tagged 48

[Mohammed Faiz]

The command to enable routing is "ip routing". It's a global level command (i.e. not in the VLAN context)

The helper address is the address of your DC.

You need an IP address in both VLANs, i.e. on both address ranges.

e.g.

ip routing
vlan 1 ip address 192.168.1.1/24
vlan 100 ip address 10.20.10.1/24
vlan 100 ip helper address 192.168.1.DC_IP

[jwc1972]

Morning

Looks good before I crash the system!

Office Switch
VLAN 1
untagged 1-40
ip helper address (domain controller)
ip address 192.168.1.* 255.255.255.0
tagged 48

VLAN 100
untagged 41-47
ip helper address (domain controller)
ip address 10.20.10.* 255.255.255.0
tagged 48

Question how does port 41-47 give out ip address of 10.20.10.* ?

[Mohammed Faiz]

The way it works (roughly) is :

A PC connected to VLAN 100 sends a DHCP request which is a broadcast packet. As the switch has an IP on VLAN 100 it sees the broadcast and forwards it (from it's VLAN 100 ip address) to the IP helper address that is configured.
Your DC receives the DHCP request and returns a DHCP offer for the 10.20.10.* range because it can see that the DHCP request was forwarded from the 10.20.10.x address of the switch.

[jwc1972]

Thank very good answer, Last queston I promise, So on the Domain Controller I can create a New Scope of 10.20.20.* to sit along side the 192.168.1.* scope

[Mohammed Faiz]

Yes, you'll need that scope on your DC. Don't forget to add a router option and enable the scope once you've created it!

[jwc1972]

Hello Again

Networks!!! I been creating a new scope of 10.5.5.11 255.255.255.0 Is this a New scope or a Muplitecast scope. We have 192.168.1.0 as the default scope?

[Mohammed Faiz]

It's just a normal scope (not a multicast scope)