Connection between 4507R and Avaya 9600 phones

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Jun 20th, 2010
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Can someone help me to understand what a DHCP option 242 is for ? I am connecting Avaya 9600 phone with our core switch 4507R.

I was requested by the subcontractor (who does avaya part) to configure option 242 on my dhcp server, since I am using my core switch as dhcp server i need to do it on my switch.

Does anybody knows how to do this by any chance?



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Aaron Harrison Sun, 06/20/2010 - 10:51
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Well - the obvious thing to do here is ask the Avaya eng these questions three:

1) Why?

2) What type of option does it need to be (IP, string, etc)?

3) What should it be set to?

That said, a quick search on google reveals this example :

Cisco phones require an option 150 to tell them where the TFTP server is, and they get further settings from there.

Avaya phones use DHCP to assign options such as QoS config, VLAN assignments and so on - as you see in the example above there is a lot of stuff that could go in there and the Avaya engineer will specify what exactly they want.

In config terms, you will go into your DHCP pool on the router and put in a command like so:

ip dhcp pool xxx

option 252 ascii "MCIPADD=,MCPORT=1719,HTTPSRVR=192.168. 1.28,HTTPDIR=1616,L2QVLAN=1,VLANTEST=0,MSGNUM=6999"

Obviuosly replacing the stuff between the quotes with the info from your Avaya eng.



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inshu.inshu Sun, 06/20/2010 - 22:32
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Thanks for your earlier reply.

I am not sure if it was a typo from your side, I am actually looking for an option 242 in DHCP.

As you asked its a STRING which they need on it.

I would come back with the answers which you had raised, even I am not sure of the same.

Is it possible to enter those STRING commands on a CISCO device??

I did see option 1-254 under DHCP pool but soon after that the switch is asking only for an IP ADDRESS.



Aaron Harrison Sun, 06/20/2010 - 23:33
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The config is the same regardless of what the option number is; the important thing is that you configure it as requested by the phone guy.

When you say you only see the option for 'ip', where are you configuring this? Are you doing it from the CLI?


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