I have a Windows 2003 server running DHCP with 5 scopes running on it. I have reserved the IP addresses for my macintosh computers because I have had to use static IP addresses because they will not recieve an IP address from the DHCP server. My XP machines recieve DHCP just fine. I finally tried bootp to recieve an IP address with the Macintosh computers and they recieve an address dynamically with bootp. I deleated the test computer from the reservation list and it would not get the bootp address. Then reserved the IP and it gets the bootp address. All of the Macintosh computers are in the same vlan and there are other XP computers in the same vlan that recieve DHCP. It has been this way since it was put into production about 2 months ago. Why are none of the macintosh computer recieveing DHCP IP addresses?
DHCP issue
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Not sure, all my mac devices receive DHCP addresses just fine. I don't normally work with windows, do you show a log of the MAC addresses requesting IPs?
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Darn man, you have 5 scopes running? Are they all active and in use, or are you just using one? If you have vlans with XP able to access DHCP, you should be ok with the Macs (that I'm aware of). My first question would be to the scopes and if you need them all or not.
I wireshark and it shows up as a Nak reply. I looked up a Nak reply and basically found out that the DHCP server is saying that that machine already has an IP address from it. But it does not. I do not see any logs showing mac addresses. Where whould that log be?
Only 2 of the scopes are not being used at the moment. The other 3 are set up for a specific network. One network is for oracle, one for the main office, and the other one for the remote offices.
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Are all those scopes running through the same NIC? First off, if you are getting a NAK, then you have at least two 'servers' fighting to give out addresses. I say servers in quotes because it could be the same server, but the scopes are fighting against each other. Where is the NAK IP address listed as? Is it a different device or the server itself? That would narrow it down.
If it's a different IP address, then you need to find out what system that is and turn it off/disable DHCP. If the NAK is coming from the server, then it can't determine what address to assign the Mac. Ideally, for multiple scopes you'd have a NIC for each scope, each NIC having only an IP address within that scope. If the Mac request is coming into a NIC with multiple scopes attached, the server can't determine which to give out, so it gives out one, then immediately issues a NAK from the other scope.
If it's a different IP address, then you need to find out what system that is and turn it off/disable DHCP. If the NAK is coming from the server, then it can't determine what address to assign the Mac. Ideally, for multiple scopes you'd have a NIC for each scope, each NIC having only an IP address within that scope. If the Mac request is coming into a NIC with multiple scopes attached, the server can't determine which to give out, so it gives out one, then immediately issues a NAK from the other scope.
The NAK is comming from the DHCP server address I believe. I can run another test when I get a little more time.
The scopes are running on the same NIC. If this is an issue why does it not happen to the PC computers. What would I possibly have to do to resolve this issue. I do not believe that I will be able to change the scopes to a different server.
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Well to test it out you could stop all but one of the scopes (the one you want the Mac's to get an address from), and then see if they can get an address.
Are the scopes all different subnets, or all part of the same subnet, just different ranges? I'm not an networking guru, but the easiest answer is to have each scope on it's own NIC. Each NIC then should be connected to whatever device is handling that subnet. If you have them all connecting into the same switch (for example), it still won't help because during a broadcast each NIC will see the request and try to answer it.
Are the scopes all different subnets, or all part of the same subnet, just different ranges? I'm not an networking guru, but the easiest answer is to have each scope on it's own NIC. Each NIC then should be connected to whatever device is handling that subnet. If you have them all connecting into the same switch (for example), it still won't help because during a broadcast each NIC will see the request and try to answer it.
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Donno, I'm not a windows person.. let alone admin 
On a *nix box I'd remove check the leases file, stop the server, fix the file and restart dhcpd.
On a *nix box I'd remove check the leases file, stop the server, fix the file and restart dhcpd.Is there any reason why the mac computers are the only ones having the issue with multiple scopes?
The scopes are different subnets running on one NIC.
There is no way that I can disable a scope because I will shut down production if I do.
What is different about a Mac DHCP request and a PC DHCP request?
I read somewhere that it could be the DHCP catch on the server that is thinking the computer has an IP address when it does not. Does anybody agree? If so how do I clear the DHCP cache and will it take down the DHCP server for a little while or not?
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I don't know about clearing the cache. I haven't done that on a DHCP server, but I suppose you could look to see if the DHCP server thinks it has issued an address to the client and delete it. Also, double check that the scope is set to issue addressed for both DHCP and BOOTP requests (Scope Properties -> Advanced Tab).
Why it would work for one and not the other? I don't know. I'm surprised it can work at all unless I'm not understanding something in your setup. If you use wireshark again, see what scope/address is issuing the acknowledgement and which is issuing the NACK.
Why it would work for one and not the other? I don't know. I'm surprised it can work at all unless I'm not understanding something in your setup. If you use wireshark again, see what scope/address is issuing the acknowledgement and which is issuing the NACK.
All of the scopes are set to DHCP only.
It does not say what scope it is trying to get the IP from. But I can tell you that it is trying to get a certain IP address. So I would assume that it is responding from that scope that the IP address is in.
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Well, if it works with the reservations in place, I'd leave the reservations for the MAC address there. It sounds like they are requesting the address from a location where the server cannot determine which scope should respond, so they are in contention over who should be issuing the address.
I found out that the Macintosh machine keeps trying to get the same IP address which is now 10.0.30.109. Using angry IP scan I saw that 10.0.30.109 is a host called tempoe, but it is not in the DHCP server as being used so I assume that it is statically assigned to that tempoe machine. I have had another computer get the 10.0.30.109 address from dhcp and now it shows up in the dhcp server and the mac computer tried to get the 10.0.30.131 and an xp machine was trying to get the same IP at the same time. They both kept getting a NAK back. I do not know what is going on. But I plugged the machine into the 20 network and it got an IP address right away.
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