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Option 125 on Win 2003 Server HELP!

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pea123

Technical User
Aug 26, 2009
380
Hie to you all.

I have disabled the DHCP on my 3300 and plan to use the Windows server.
Have configured options 125, 128, 129 & 130 on the Windows DHCP.

This works fine but my worry is that the IP phones come up using option 128+ and not using option 125.
If I connect the IP phone straight to the 3300 and use its DHCP enabled the phone uses option 125.
Why is that? My Option 125 is as follows:-
Class: Global
Name: Mitel
Data Type: String
Code: 125
Description: Mitel option 125

String Value:-> id:ipphone.mitel.com;sw_tftp=10.188.14.2;call_srv=10.188.14.2;dscp=46v46s26

Why do the phones prefer not to use the Option 125? What am I doing wrong?
 
You are not doing anything wrong

128, 129 and 130 are perfectly fine

125 is preferred because it is licensed by Mitel and not subject to use be other vendors

To set up 125 on your server you will need a copy of the DHCP helper program to create the array for you

**********************************************
What's most important is that you realise ... There is no spoon.
 
Certain phones will use the older options out of the box and need a firmware refresh before they pickup option 125. Option 125 was introduced becuase they was an issue where other products needed to use options 128, 129 and 130. If possible I always use the 3300 to service the phones not a fan of using an external DHCP server.

I'd tell you a UDP joke but I'm afraid you won't get it. TCP jokes are the best because you always get them.
 
Thank you all for your response. I managed to make the phones use option 125 by using the DHCP helper program.
 
The customer for the above setup has decide to come up with 2 vlans: vlan 1= data & vlan 20= voice. The problem is that the Win DHCP server is now on the data vlan 1 & the 3300 on vlan 20. The vlans have been put on the cisco switches.The Mitel options are still there on the Win DHCP server but the phones are not coming up.They display Naks/lease over> resetting . If I assign static DHCP values on the phones they come up. From here onwards I am completely lost.
Please help me in detail about what to check.
 
You should add on the DHCP option 125 on the Windows box:

vlan=20;

like:

id:ipphone.mitel.com;sw_tftp=10.188.14.2;call_srv=10.188.14.2;dscp=46v46s26;vlan=20

:code.poet:
 
pea123 when you say the VLAN's are in the Cisco do you mean that the Cisco layer 2 switches have a voice VLAN programmed in them so that if they detect a voice device they then tell the voice device to go to VLAN 20? The Cisco switches can do this via CDP. If that is happening then the phone issue their DHCP request on VLAN 20 and you would need to send the DHCP request back over to the data VLAN or setup the internal DHCP server in the 3300 controller with all the necessary information.

I'd tell you a UDP joke but I'm afraid you won't get it. TCP jokes are the best because you always get them.
 
If you are confused about VLAN and tag/untag; and want to use the phones' internal switch for data, I suggest you bring in an IT expert. Your switch works best if it supports LLDP.
 
Cisco still support LLDP?

I'd tell you a UDP joke but I'm afraid you won't get it. TCP jokes are the best because you always get them.
 
Is LLDP not caklled CDP on Cisco? does the same thing anyway...IIUIC.
 
LLDP is kind of an industry standard and CDP is not. Cisco at one time supported LLDP but thought I remember something about them dropping it in favour of their protrocol called CDP ( Cisco Discovery Protocol ). Maybe its the other way around and other vendors are staying away from CDP. Can't remember <sigh>

Anyway whether you use CDP or LLDP these protocols are used to allow a device to advertise its requirements to the layer 2 ( things like PoE power requirements ). On boot the Mitel sets say "hey I am a voice device" The layer 2 sees that and says "ok you belong on VLAN x" which if the lyaer 2 is programmed correctly will be a voice VLAN. The set then starts taggin its packets to that VLAN ( even DHCP requests ). At that point the set is trying to talk to a DHCP server on the voice VLAN. Either you put a DHCP server there ( most cases the 3300 its self ) or you need to use DHCP forwarding/helper to send the DHCP request back to the data VLAN where the corporate DHCP server is. You need to do that for MXE Servers, ISS installs and vMCD deployments if there is no physical MCD on the voice VLAN ( i.e those products don't have an internal DHCP server ).

Don't know if this helps or if I am just rambling. Maybe I need another coffee.



I'd tell you a UDP joke but I'm afraid you won't get it. TCP jokes are the best because you always get them.
 
Yes, loopy it makes sense.

Didn't have the patience to write it up! As for CDP vs LLDP, stop talking; Cisco is watching! They know better and will remind you of it; why keep it simple when there is Cisco?!
 
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