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New Member

DHCP Blocked by VLAN

We have a server that we remove from the rack. The only role it has is to give out DHCP on the wireless network. I tried enabling  the built in DHCP server on  the Airespace 4112, though a Catalyst 3750G, but I dont get an address when I'm connected to the wireless network even though the range is enabled. If I set an static IP on my wireless card I can access the network. I also tried enabling DHCP on a Sonicwall that is connected to the Catalyst 3750G.

Do I need to link the DHCP scope to the wireless network?

Is there anything on the switch that would be blocking DCHP since it on a VLAN?

I have the last four ports in a VLAN for the AP's and the internet connection to the Sonciwall.

Thanks fort the help.

Everyone's tags (6)
1 ACCEPTED SOLUTION

Accepted Solutions
Purple

DHCP Blocked by VLAN

Hi,

go to the interface VLAN where your client are and modify the ip helper-address if necessary.

Regards.

Alain

Don't forget to rate helpful posts.
6 REPLIES
New Member

DHCP Blocked by VLAN

Did you delete the existing DHCP scopes on the server?  Also, what was the old IP of the server?  When you re-added it to the network did you use the same IP address?  Have you made any other changes to the server/network (particularly network/gateway/routing changes)?

Thanks,

Sean Brown

http://www.sleepyshark.com

New Member

DHCP Blocked by VLAN

I didnt delete the scope I just unplugged the server so it wouldnt give out DHCP.

I didnt re-add it since I want to use the Airespace built in DHCP server. For now we have the old server plugged in giving out DHCP till I can track down why the only thing that can give out DHCP is the server.

Purple

DHCP Blocked by VLAN

Hi,

is the DHCP server on a different subnet than the clients? if so have you updated the ip helper-address to point to the new DHCP server? and also does the new DHCP server knows how to get to this subnet( with a static route for example)?

Regards.

Alain

Don't forget to rate helpful posts.
New Member

DHCP Blocked by VLAN

Ill check the server but I'm pretty sure that its on the same subent.

Where do I update the ip helper-address?

Purple

DHCP Blocked by VLAN

Hi,

go to the interface VLAN where your client are and modify the ip helper-address if necessary.

Regards.

Alain

Don't forget to rate helpful posts.
New Member

DHCP Blocked by VLAN

I ended up using the override DHCP option in the Airespace and pointing the ip to itself.

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