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Win2k3 DHCP issues in a Multi-VLAN Environment

Posted on 2009-05-02
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Last Modified: 2012-05-06
I have read evey post I can on DHCP in eperts-exchange, but I am still having problems with DHCP.  It is one of those things until about 3 months ago, just worked....well not anymore, ugh!
Issue:  
Workstation in many of the VLANs take an unreal amount of time to get an IP address, but not everywhere. I am getting NAK errors on the workstation, I am getting a ton of renew requests on a DHCP server when I add a new machine in the DHCP logs.  The machines eventually all get an IP address and work great, but if they reboot, or shutdown...the problem starts all over.
It appears that the DHCP server is getting the request fine from the client, but the client never knows that the address has been assigned.  Eventually is works, but it takes anywhere from 3mins to 1 hour.... :(   If you disable/enable the NIC on the client sometimes that will make it work faster, but not always.


Environment:
-I have multiple VLANS across multiple sites.
-I have Cisco Routers
-I am running AD (Specifically Win2K3 R2 fully patched DCs)
-I am running DHCP and DNS on the Domain Controllers.
-I have verified Authorization of all DHCP servers (unauthorized and reauthorized without issue)
-I have 6 DHCP servers in multple locations. I added one on a site specifically to troubleshoot this issue trying to mitigate potential router/switch config issues.
-All inter-site connections are either 1gb fiber or 100mb fiber...I don't think network traffic is the issue.
-I have about 650 workstation across multiple sites.
-24X7X365 Hospitals

What I have done so far:
-I have read tons online and I am close, but still having the issue.
-I have looked for rogue DHCP servers however I am not 100% sure I have been completely successfull on this.  DHCPloc from a client machine always throughs a:
OpenReceiveSocket failed 10049. (tried Win2k3 svr and winxp wks)
-I have used Wireshark and have it installed on every DHCP server to see if I can find the issues.  
-I have test DHCP settings with DNS Dynamic Updates both on and off (no difference that I can tell).


This is some of the logs from the DHCP server (with DNS updates off for cleaner logs)
The machine wks :MHC80711C.mhc.LCSS.local
I did a release and renew and this is what I got:
12,05/02/09,06:43:15,Release,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:18,Renew,172.20.23.5,CME0249.mhc.lcss.local,008064731050,
10,05/02/09,06:43:19,Assign,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:20,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:21,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:22,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:23,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:24,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:43:24,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:25,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:26,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:27,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:28,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:29,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:30,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:31,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:32,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:33,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:34,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:35,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:36,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:37,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:38,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:39,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:43:39,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:40,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:41,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:42,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:43,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:44,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:45,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:46,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:47,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:48,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:49,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:50,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:43:50,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:51,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:52,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:53,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:54,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:55,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:56,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:57,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:58,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:43:59,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:00,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:01,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:02,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:44:02,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:03,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:04,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:05,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:06,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:07,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:08,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:09,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:10,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:44:10,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:11,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:12,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:13,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:14,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:15,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:16,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:17,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:18,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:19,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:20,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:21,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:44:21,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:22,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:23,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:24,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:25,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:26,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:27,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:28,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:29,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:30,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:31,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:32,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:33,Renew,172.20.20.73,,0004EA092503,
11,05/02/09,06:44:33,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:34,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:35,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:36,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:37,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:38,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:39,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:40,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:41,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:42,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:43,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:44,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:45,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:46,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:47,Renew,172.20.20.65,MHC80711C.mhc.LCSS.local,001279A3E772,
11,05/02/09,06:44:48,Renew,172.20.20.73,,0004EA092503,

I have attached a Wireshark image too for this same exact time with Bootp.DHCP as the only filter.

I am running out of ideas!  Any helps would be greatly appreciated...!!!


wireshark-image.JPG
0
Comment
Question by:BrooksBetts
  • 10
  • 9
19 Comments
 
LVL 7

Expert Comment

by:blue-screen
ID: 24287240
The DHCP NAK from 0.0.0.0 is curious.  What is the MAC address sending the NAK?

172.20.2.6 is the server, right?

For transaction AA34BB4D, the device at 172.20.20.1 NAKs the address given to it.  Probably because it detected a duplicate IP?  Check the event log of the host.

Maybe you have a misconfigured router (e.g. wrong subnet mask) which is sending proxy-arp replies to duplicate address ARP probes.  In that case, all devices on that segment (VLAN) will NAK addresses since they thing the addresses are duplcates.

Without knowing more about your whole seup, it is hard to say.

NAK scenarios listed at
http://blogs.technet.com/teamdhcp/archive/2006/10/26/when-is-dhcp-nak-issued.aspx

Sp from that, it is more likely that the DHCP server is misconfigured, offering addresses which are not valid for the subnet on which it is located?

Are you using helper addresses to a central DHCP server?  

Can you post the whole CAP file?
0
 

Author Comment

by:BrooksBetts
ID: 24287353
Hey Blues-Screen Thanks,

The DHCP server is 172.20.2.6 corect?
Interseting that you point out the MAC of the source sending the NAK 0.0.0.0  Not sure...I am going to have to run the capture again and I will attach the whole Cap File.
Yes we are using IP Helper-address for each VLAN pointing to the specific DHCP that hosts that scope.  We have run like this for at least 4 years without issue and then several months ago...here we go.  I am not a Cisco guy so I we could have something wrong there.  I will have a guy take a look at it for me on Monday.
I will attach the CAP file once I have a chance to run the test again.
Thanks again,
Brooks
0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24287445
It sounds like you might have a mask mismatch between the DHCP scope and the router interfaces.  The helpered DHCP packets contain ONLY the IP address of the helpering device (the router interface) so it will pick the scope in which that address falls.

HOWEVER.  If the scope is LARGER than the interface mask range, the DHCP server will return an address which is out of range for that subnet, resulting in a NAK.  This would also explain why it works sometimes and fails other times - if it deals out a valid address, it will be accepted, but if it deals an out-of-range address it will be NAKed.

Check the mask of your scope against the subnet masks on the router interfaces. Also be fore that DHCP excludes static addresses in use, including the router IP adddress.  It could also just be that you've run out of IP addresses or have failed to exclude statically assigned addresses on that network.
0
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Author Comment

by:BrooksBetts
ID: 24293967
Hey Blue-Screen
Thanks for the info and sorry for the delay.
One of your points was right on...I had a mis-match subnet Mask on the router and the scope.  I had to move the scope to another server so as not to creat overlap.  I just test again and I am still getting the same issue. Darn...I was really hopeful that was it.
I have attached snapshots of the VLAN config from the router and the scope.
The DHCP server is now 172.20.2.14 (since I moved it).
The Workstation is now 172.20.20.177 (in the new scope)
I have also attached a cap file that I got after making these changes.

VLAN config from Router:
!
interface Vlan12
 ip address 172.20.20.1 255.255.254.0
 ip helper-address 172.20.2.14
 no ip redirects
 ip ospf priority 50
 mls rp vtp-domain MHC
!

I verified there are not Statics/reservations in this range.
Thanks,
Brooks
Nursing-School-DHCP-Scope.JPG
MMHMHCDC2.txt
0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24294923
Move to another server...?  Do you have more than one DHCP server?  Are they synchronized with each other?
0
 

Author Comment

by:BrooksBetts
ID: 24295012
Hey Blue-screen
No, I left the original scope on the old DHCP server, but I created an exception for the entire scope on that server (DHCP server 172.20.2.6).  I then created a scope on another server (172.20.2.14) in that same VLAN for a different range of IP addresses in the scope.  I had to then update the helper address on the Cisco to point to the new DHCP server.   The reason I did this is the Subnet mask was wrong on the old scope, but I could not edit it.  In my reading I found that it was not good to deactivate a scope with active leases.  The article I read from MS was that you need to create an exception for the entire scope and wait for all the leases to expire before you blow that scope away.  This problem is happening with multiple VLANs (not all of them).  Hope this helps a little!
0
 

Author Comment

by:BrooksBetts
ID: 24297256
Hey Blue-Screen,
 I am not sure if I put you off with my last entry.
Yes I do have multiple DHCP servers, but they are setup to host different scopes for other VLANs.
I use the IP Helper address on the router to tell each subnet where to get their DHCP from.  I hope that makes a little bit more sense.  I have howerver been kicking around the Idea to resolve this problem to consolidate all VLAN scopes to one server.  Until recently with this problem, we have run like this without issue and that is why I am so perplexed on the issue.

Thanks again,
Brooks
0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24297703
OK, I see that 172.20.20.177 is offered, but NAKed.

Is that a valid address for the subnet with the helper address?

Is it a duplicate?

The problem is you have lots of active leases from the old server still in play, and it looks like the DHCP server keeps offering 172.20.20.1777 no matter who asks

Client MAC address: HewlettP_a3:e7:72 (00:12:79:a3:e7:72) is the asker here, and the Cisco or HP  keeps NAKing that address.  (After ACKing it, oddly enough)

Would be interesting to see what the Cisco device thinks is going on.  (Debug IP UDP. I think?)  Or even the event log of the HP host.

0
 

Author Comment

by:BrooksBetts
ID: 24298349
Hey Blue-Screen

The 172.20.20.177 is a valid address for that subnet.
The subnet is 172.20.20.x/23 so that should include 172.20.20.1 - 172.20.21.254
It should not be a duplicate as I currently only have one scope giving out the addresses for that subnet
on the DHCP server of 172.20.2.14.  The scop goes from 172.20.20.176 - 172.20.20.254.

-I have attached the Workstation System Event log screen shot. (Cleared right before a releease and renew of the IP address).
-I have attached the results of the Debug IP UDP from the router at that same time (little hard to stop and start) but it caught the multiple requests by the workstation and the multiple sends to the workstation.
-I also attached another Cisco Debug Debug ip dhcp server packet for further information.
I am still drawing blank.

I really appreaciate your help so far, you have given me a ton of things to look at that I did not think of on my own.

-Brooks
debug-ip-udp.txt
debug-ip-dhcp-server-packet.txt
Workstation-Eventlog.JPG
0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24301667
Weird.  The router looks like it is doing all of the right things and yet the workstation is getting a NAK from somewhere?  A NAK every second.

Looking at the capture, the NAK is coming from the Cisco MAC address, but an IP address of 0.0.0.0!

The only thing I can figure is that the router is failing to create the ARP entry to make the final delivery of the DHCP ACK to the end host, but gets an ARP reply for the IP address which it is trying to assign to the host.  This can be possible if there is some router on the wire with a mismatched subnet mask AND proxy-arp enabled.

debug ip arp is the next step on the Cisco.  If you ping the address in question, you may not get a reply but check to see if an ARP entry is created.  If so, locate that MAC address - he is the rogue arp responder.

0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24301769
On further reflection, I'd like to see a packet trace from the HP DHCP client.  Perhaps there is a rogue DHCP server on that segment?  I'd like to know why there is an ACK followed by a NAK.  That just ain't right.
0
 

Author Comment

by:BrooksBetts
ID: 24303015
Hey Blue-Screen,
 Thanks!  Just to make sure I understand the test to run.  When you say: "If you ping the address in question, you may not get a reply but check to see if an ARP entry is created.  If so, locate that MAC address - he is the rogue arp responder."
What IP are you referring to?  the workstation IP? and do I ping that from the router or from another workstation?
I will put wireshark on the workstation while I do this...I had not thought of that, but it makes sense.
I really appreciate you sticking with me on this!!!!
-Brooks
0
 

Author Comment

by:BrooksBetts
ID: 24304011
Attached is the Cap FIle from the workstation
workstation-Cap-files.txt
0
 
LVL 7

Accepted Solution

by:
blue-screen earned 2000 total points
ID: 24304693
OK that capture file has the smoking gun.  From 758 is an example:

Ethernet II, Src: Proxim_91:bc:17 (00:20:a6:91:bc:17)

is sending the DHCP NAK.  Find that device, and figure out what it's problem is.  

Using the filter
eth.src == 00:20:a6:91:bc:17

It seems that the IP address of the offending device is 172.20.20.178, and it is sending IAP packets, which leads me to believe it is a misconfigured access point.

You're welcome.

0
 

Author Comment

by:BrooksBetts
ID: 24308051
Hey Blue-Screen,
That was it!!!!
I tried six ways to sunday to fix that AP by reloading the firmware, reconfiguring and nothing made a difference.  If that AP was on the network, I got the NAK issues.  You nailed it!
Thanks a bunch.  I am now going to apply what I learned to some of my other subnets, but I am fairly certiain that I will find this same issue in my other subnets as I have these Proxim's everywhere.
They are Proxim AP700 just incase someone else has an issue.
Thanks agian!!!
-Brooks
0
 

Author Closing Comment

by:BrooksBetts
ID: 31577161
Thanks Blue-Screen,  I cannot tell you how much I appreciate your help on this!
0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24310067
Check the subnet mask of the AP and also make sure proxy arp is OFF.  A call to Proxim tech support is in order, add a note here if you learn more about why the Proxims interfere with DHCP.

0
 

Author Comment

by:BrooksBetts
ID: 24312655
Okay, so here is what I found.  We have out 60 Proxim AP-700 Access Points on our network.  They are scattered on all of our VLANS at the different facilities.
Recently we upgraded all of the AP's via our ProximVision Central Managment to Firmware Version 4.0.0
Only some of those AP's actually took the update.
Well once Blue-Screen turned me on to the Proxim AP being the issue we found that everywhere we had a AP-700 running firmware version 4.0.0 we were getting the NAK issues.  We called Proxim and they were aware of this issue and had fixed in firmware versions 4.0.1 and 4.0.2.
We applied the 4.0.2 and that cured the issue.  My comment above about trying to upgrade the firmware to resolve the issue; well I discovered the firmware upgrade failed and it stayed at 4.0.0 so I was close, but it did not work.
Anyway, if you have an AP-700 running Firmware version 4.0.0 be ready for DHCP NAK issues.
This is why we only had the issue on some of the segments of our network....!
I cannot tell you how many hours I spent troubleshooting this issue and Blue-Screen nailed in in about 2 days....thanks!
On to the next problem :)
0
 
LVL 7

Expert Comment

by:blue-screen
ID: 24315042
Your first question with EVERY network problem should be "what changed?" :-)
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