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  • Status: Solved
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DHCP issues

I've been having this problem now for a few weeks at least.  Throughout the day, different clients, usually between 2 to 6 clients, can't connect to the DHCP server to get an IP address.
I've restarted the PCs (includes both PCs and Macs), and the DHCP server has about 80 IPs available.  I have even created a new server, win 2k8 R2, in which I moved my DHCP server from win 2k3 to 2k8 R2, and it's still doing the same thing.  

The server is authorized, as everything else is working fine.  It's been so speratic that it's happening to PCs on different switches, so I can't say it's only been happening to PC's on only 1 switch, but it's been affecting maybe 5 or 6 different switchs.

I'm just so puzzeled, I don't know what else to try to get this working.  When I assign a static IP address, it works fine.  The problem is that I only have 3 static IP address left, so that's not an option.  I really need some help, as I don't know what else to do.  I have restarted the DHCP server service, and but still no go.   The DHCp server is authorized, as when I go to properties, it gives me the option of "unauthorize", so it's authorized.

 I have a dell 6024 switch that does all the internal routing, can that be having issues?
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afacts
Asked:
afacts
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2 Solutions
 
afactsAuthor Commented:
I looked through the DHCP log, but I dont see anything out of the ordinary.
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afactsAuthor Commented:
I have uploaded my DHCP log, maybe I'm missing something, but what is strange is with IP 192.168.100.144, it's all over the place.  Is there something up with this IP?  I have added it to the address pool exclusion range.
DhcpSrvLog-Tue.log
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netballiCommented:
after viewing your DHCP log it appears your DHCP is catering to more that a few domains it that true also can you verify the scope options you have set on you DHCP.

15,09/11/12,00:22:25,NACK,192.168.100.113,rledesma.domain.com,0019D1E6FF8C,,0,6,,,
15,09/11/12,00:22:25,NACK,192.168.100.113,esmalling2.domain.com,70CD60AA312F,,0,6,,,
11,09/11/12,00:25:59,Renew,192.168.101.107,Apple-TV.domain.com,98D6BB240740,,1486900862,0,,,
11,09/11/12,00:26:15,Renew,192.168.100.189,T1785.domain.com,001570A79370,,2103313472,0,,,
11,09/11/12,00:29:21,Renew,192.168.100.111,hthompson.domain.com,BC305BAF110C,,1971255086,0,,,
32,09/11/12,00:34:07,DNS Update Successful,192.168.100.137,jdasilva.domain.com,,,0,6,,,
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afactsAuthor Commented:
what do you mean?  No, I only have 1 domain.  Of course it's not domain.com, I changed it for security issues, but what doyou mean by catering to more then 1 domain?
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afactsAuthor Commented:
what exactly do you want me to check in the scope options?
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BillBondoCommented:
11,09/11/12,00:25:59,Renew,192.168.101.107,Apple-TV.domain.com,98D6BB240740,

I believe netballi is referring to this ip address
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afactsAuthor Commented:
oh, yes, I have 2 subnets, actually, I have 3, also .200 as well for my VoIP phones.

Actually, I've discovered that it's probably not a DHCP issue, as I just did a release and renew on my PC and it's working fine, I got a different IP address.
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netballiCommented:
Good to hear you issue is resolved but as a best practice you should look at you lease time and amend it as per your network size if it is small to medium lease time should be long say 16 to 24 day and if you network is large it should be short say 7 days.
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afactsAuthor Commented:
My lease time is 1 day, small network.  The issue is not resolved, I just don't think it's my dhcp server.
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afactsAuthor Commented:
I tried plugging in the mac in question in 2 other switches, and same thing, it doesnt get  valid IP.  In One switch, it got the 169.xxx.xxx.xxx IP, but the other two switches, nothing at all.
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afactsAuthor Commented:
It is a DHCP problem.  I assigned a static IP to the mac and it works fine.

So it's not with the switches, it's with the DHCP server. I restarted a few of the phones, and same issue, not getting an IP address.
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afactsAuthor Commented:
Check this out, this doesn't look normal, how could there be the same devices with almost the same MAC address?
dhcp.jpg
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afactsAuthor Commented:
Thanks guys, I figured out the problem, my DHCP server was still handing out IPs that were taken.  As soon as I enabled the IP conflict reslution, I set it to 3 pings, since then, I haven't had a problem yet.
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