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Trying to join a osx machine on a dhcp network which forces certain client IDs.

Even if I was to modify the client-id via the network properties, the DHCP server is not accepting this request, since Windows and Apple send this via different options

You can set the ClassID in the Network Control Panel in the DHCP Client ID box. The trick lies in setting up your DHCP server to recognize it. Windows XP sends the DHCP class ID via DHCP option 77, and OS X sends it via option 61. You'll have to set your DHCP server to check for option 61, +with an offset of 1 and a length of 9+. That's the tricky bit.

So, without modifying the DHCP server... (which does not belong to me), is there anything that can be done on OSX to modify the client-id option to be 77?

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up vote 1 down vote accepted

You could try watching a dhcpdump off of a test linux dhcp server to see if the OSX client is offering anything for option 77.

Outside of that you could look into using networksetup a look around the man pages didn't show anything useful other than what looks like a cli way to set what you've been doing in the GUI.

Lastly it looks like you could install a more robust dhcp client, dhcp, with macports and use that to define things more granularly.

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Thanks Tawm! Will keep this thread uptodate... dont have time to work on this right now, but if i get an update, then i'll update :) – CMag Dec 5 '11 at 15:40

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