iMac refuses to accept IP

[Siegenthaler Tina]

>> 
>> Can you capture the second discover from the new client and take a look
>> at the Client Identifier? My guess is that the second packet contains a
>> 7 byte CI (just like the older clients) consisting of 0x01 and the MAC
>> address (013C075472CBC2). The value above seems to be those 7 bytes and
>> then 26 bytes of zero, which is not the same.
>> 
>> Client Identifier is always the key from the server's perspective. If CI
>> changes it's a new host. This is mandatory per RFC2131/RFC4361.
>> 
>> If that's the problem there is no DHCP compliant way of solving the
>> problem other than changing what the client sends as CI.
>> 
>> -- 
>> 
> 
> Hi Peter
> 
> Ah - yes. That sounds very plausible and I'll check that tomorrow morning first thing. It would explain why the DHCP server doesn't simply offer the same IP again on the second discover. I had been wondering as to why that was, because usually, the DHCP server will happily do so even if the old lease has not yet expired.
> If that is really the case, it will be difficult to change it on the client side, since this behavior is probably sitting somewhere in the firmware. I wonder if a different boot manager woul help here? Hm. Maybe I'll give it a try with rEFIt.
> 

Indeed. This is the client identifier option of the first discover:

    Option: (t=61,l=33) Client identifier
        Option: (61) Client identifier
        Length: 33
        Value: 013C075472CBC20000000000000000000000000000000000...


And this the one of the second:

    Option: (t=61,l=7) Client identifier
        Option: (61) Client identifier
        Length: 7
        Value: 013C075472CBC2
        Hardware type: Ethernet
        Client MAC address: 3c:07:54:72:cb:c2 (3c:07:54:72:cb:c2)


Now that this is clear, I'll just have to find a workaround...

I'm going to try the following:

- Setting a DHCP client ID in the System Prefs (as proposed by Simon - thanks)
- If that doesn't help, use rEFIt as the boot manager
- If that doesn't help either.... ???


Tina