I want my DHCP server on VLAN 10 to hand out IP's to all the devices on the 3 VLANS. The network consists of Windows 2008 servers and Cisco 3750 and SG 500 switches. I know I need to configure the 2750 switch to route traffic to the VLANs but how does the pc's and IP phones on 50 and 150 get the IP from the DHCP server on 10? Will the dhcp request pass through the router? Are there optons on th edhcp server Ishould set?
Is this the correct commands needed on all switches?
1. enable
2. configure terminal
3. interface vlan 150
4. ip helper-address 192.168.10.10
Predrag Jovic
You don't need commands on all switches. You need it just on vlan interface (you don't need to configure vlan interface on every switch - I'm not familiar with your network design, but I guess that you need to do that just on your 3750 switch vlan interfaces).
But ... commands are correct.
NytroZ
ASKER
I added the commands to the VLAN 150 interface on the 3750 switch but the client still cannot receive an IP from the dhcp server. The client is in VLAN 150 which is configured on the SG500 switch. the SG500 is connected through the trunk port to the 3750 switch which has the VLAN 150 added to it. The client can ping the dhcp server and the dhcp server can ping the client. The DHCP server is located on VLAN 10 on the 3750.
Try on another switch to set ip helper-address - that should be on switch where you do your inter vlan routing. (I guess it is not on your 3750).
NytroZ
ASKER
no, you are right. It is on the 3750 where the inter vlan routing is done.
Craig Beck
Ideally the DHCP server should be using the 3750 as its default gateway, or you should add static routes on the DHCP server to the subnets via the 3750's address on VLAN10.
Predrag showed me the command I needed on the switch to allow it to pass the dhcp request to the server. You helped me with the scope. So there were really two tasks needed to get it to work. Thanks to both of you!
1. enable
2. configure terminal
3. interface vlan 150
4. ip helper-address 192.168.10.10