Dear fellow EduGeekers!
It isn't very often I need to ask for help, but unfortunately I'm very much so a "Microsoft Man" so when I'm faced with some college Intel Mac's which aren't getting DHCP addresses on their wired ethernet adapters - I just get stuck.
The Mac's take as long as 15 minutes to get an IP address. Only very occasionally does it give up and get an APIPA, for the most part when I click "Renew DHCP Lease" nothing appears to happen until out of the corner of my eye I notice it eventually populates the correct IP address.
Here's some facts:
The DHCP server is our primary DC running our primary DNS. It is Windows Server 2003 R2.
They are using the same VLAN and same DHCP server as our Windows clients - which work fine
AirPort DHCP works fine. Again, this is the same DHCP server, but it is a different VLAN (this is currently our workaround)
The problem has only reared its head in the last few weeks - prior to this it has been working for many years (albeit managed by my predecessor who was somewhat a "Mac Man" in comparison)
The problem affects all Macs including Mac Mini, iMac and Macbook
The firewall is set to "Allow all incoming connections" so unless there's a separately managed list of allowed/denied ports, then DHCP requests shouldn't be blocked by any firewall.
Occasionally when I click on "Renew DHCP Lease" the previously assigned IP address, subnet mask and gateway address appear, then straight away disappears and then it takes 10-15 minutes to actually renew the lease.
Due to a lack of decent Mac knowledge, I can't say I have tried much. What I have tried is adding an address reservation for the Mac's on the DHCP server in the hope that this would accelerate the procedure, but unfortunately the same problem exists and all of the clients experience a long delay before getting an address.
On the Windows side of things I am going to inspect logs and events generated to see if I can relate anything to the error and perhaps setup some sort of network monitor on the DHCP server to see the actual requests coming in; or not as the case may be.
Apart from this, I am struggling and I hope it's something pretty basic I have missed and also I am stuck when it comes to the Mac side of things so if anyone can suggest literally anything to try (even if it is 1st day of school type stuff I might have missed - yes there is an ethernet cable connected, by the way ) then it would be much appreciated.
Thank you.