VLAN not reporting to DHCP SCOPE

Edgar Veloz
Edgar Veloz used Ask the Experts™
on
I have a Vlan set in one Layer3 Dell 6248 switch, this vlan purpose is to connect our PBX, I have two subnets, my Native has the scope 192.168.16.0/24 and the vlan 7 has 10.11.0.0/24 now if I have my facts right I created the vlan in the switch  and gave it IP 10.11.0.5 255.255.255.0 with IP Helper Address 192.168.16.40 that in it self should be able to route to my DHCP server where I created the 10.11.0.0 scope, I think that I have everything cover so I can plug phones into the switch and they will be able to reach the 10.11.0.0 subnet to get an IP from that scope but I connect the phones that are programmed to look for vlan 7 and they cannot reach, but some of my devices that are in 192.168.16.0 scope are reporting to the  10.11.0.0 scope, can anyone help me to understand what did I do wrong ?
Switch.JPG
DHCP.JPG
Comment
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®

Commented:
First, if you have 2 VLANs and your one DHCP server is handing out addresses for both VLANs, check the port your DHCP server is connected to and make sure its a trunk port and that all the necessary VLANs are set to it.  

An easier way to do it if you have available ports on your DHCP server is connect one port up to the switch an an Access port, give it the VLAN the 192.168.16.0/24 is on and then connect another port up as another access port for VLAN 7.  Make sure the devices for VLAN 7 are access only and then they should get the right addresses.
Edgar VelozIT Consultant

Author

Commented:
Yes I think I can see what you mean the only problem I have is that my DHCP is Hyper-V so I really don't know how to trunk separate ports from that point, I'm sorry I realize that I didn't post that part in my initial question. I think that having the traffic running on two different ports to a set trunks can do the trick but since is VM that presents a challenge on it's own.
Commented:
That's not really a problem.

This is what you can do.  You can add a second network adapter to the VM.  The first one will be your current IP address that hands out 192.168.16.0/24 and the second one will be on 10.11.0.0/24.

You can specific in the VM's network adapter which VLAN it is on.  So if the Hyper-V Host server is already connected to the switch port that is trunked for the VLAN's, then when you setup the VM's network adapter with different VLANs it will work.

Does that make sense?
Edgar VelozIT Consultant

Author

Commented:
Yes it does thanks I'll try and I will get back to you on this

Thanks once again.
there is no requirement to trunk the second VLAN to the DHCP server, thats what the helper address on the L3 switch is for

obviously the DHCP server has to have a suitable DHCP scope for the non local addresses

from what you have described, I would guess that your patching does not match what is configured on the switch

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial