Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations Mike Lewis on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

DHCP option 132 issues 1

Status
Not open for further replies.

quinalt

IS-IT--Management
Mar 1, 2008
11
US
A little background:

Cisco 2150 router
Adtran 1224 PoE switch - all trunk ports except 3300 uplink
3300 ICP running Rev: 8.0.8.8
5224 and 5212 phones

LAN is logically segmented into VLAN 1 (data) and VLAN 2 (voice). DHCP for the data vlan and inter-vlan routing is being handled by the router. The following options have been setup in the router DHCP scope:

option 128 ip 10.0.3.2
option 129 ip 10.0.3.2
option 130 ascii "MITEL IP PHONE"
option 132 hex 02
option 134 hex 2e

When the phones boot, they pickup a data subnet address (from the router) as expected. However, after releasing the data subnet IP, the phone displays VLAN 435297534 (or similar value). Eventually DHCP will timeout because that VLAN doesn't exist, the phone will reset and repeat the process. I've confirmed with a packet trace (via a mirrored switchport) that the router is actually providing the correct value (2).

Other info:
- If I statically set the phones to VLAN 2 they work like champs...however, this environment will have in excess of 300 phones, so statically setting them is not my first choice :).
- Also, if I omit Option 132, the phones will bootup on the data subnet and communicate with the 3300 via the router, which is OK, but will create a host of other issues.
- I've experimented with changing the data type for Option 132 in the scope but ended up with the same results.

I've set this up numerous times on a Windows DHCP server without any issue whatsoever, so I'm completely stumped as to why it would be different on a router. I can provide more detail if needed.

Any help would be greatly appreciated.

Thanks!
 
. For a Cisco® Router DHCP server, make
sure that the option type is set to hex, and
padded with 0s (for example, 0x00000002
for VLAN 2).
4. For the controller internal DHCP server, set
the option type to numeric.


Hope it helps
 
I'll give it a try and post back.

Thank you!
 
Padding the value with leading zeros worked perfectly.

Thank you.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top