DHCP option 43 instance x

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Jul 29th, 2010
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A client asked me to config different instances in dhcp.

He gave me the following config:

option 43 instance 3 ip
option 43 instance 4 hex 5060
option 43 instance 5 hex 5060
option 43 instance 7 hex 06
option 43 instance 8 hex 05
option 43 instance 19 ip
option 43 instance 20 hex 5060

"5060" in hex should be "13c4"

This config is being accepted without the instances but not with the "instance x" keyword.

hostname(dhcp-config)#option 43 hex 13c4

hostname(dhcp-config)#option 43 instance 3 ip
% Option 43, instance 3 is illegal. Zero is the only valid instance.

Could somebody be so kind to explain me if this is possible and how I should configure this?



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Steven Holl Thu, 07/29/2010 - 11:00
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  • Cisco Employee,

This isn't a voice related question, so you may get a better response in a different technology forum.

It looks like DHCP option 43 is related to WLAN configurations, so perhaps try asking this question in the wireless forum.


fab5freddy Thu, 07/29/2010 - 11:18
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Thank you for the response but this is a voice implementation.

In the meanwhile I found a example from a Siemens setup:


While Cisco phones use CDP to discover vlan, TFTP server etc

Non Cisco phones sometimes use option 43.

Allthough the phones aren't Cisco the router is.



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