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Ian PriceFlag for United Kingdom of Great Britain and Northern Ireland

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Removing DHCP Server and Clients are not getting address from new server i've installed.

Ok so I want to decommission one of my servers about the only role it's got left on it is DHCP. I unauthorised the server and de-activated the scope. I then set up DHCP on another server and authorised and activated the scope. First of all I used the same number range and then I changed it so the scope wasn't over lapping with the scope.

Client are not seeing receiving the new addresses from the new DHCP server it just come up with an error as if it looking for the old server which isn't there.

I looked on the net but can't find anything that will help

Any advice would be great

Thanks
Ian.
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bbao
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how many subnets are there in your networks? did your old DHCP server manage any scope not on its own subnet?
When you say the client came up with an error - what's the error and where are you seeing it?  Can you do an ipconfig /all and show the output here?  Wouldn't hurt to try an ipconfig /release and an ipconfig /renew.
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Bing CISM / CISSP = Only one subnet & no only managed it's own.

dipersp = It's basically a timeout message see below

C:\Users\ns>ipconfig /renew

Windows IP Configuration

An error occurred while renewing interface Local Area Connection : unable to contact your DHCP server.
Request has timed out.

dipersp = This is ipconfig if I turn the old server back on

C:\Users\ns>ipconfig /all

Windows IP Configuration

   Host Name . . . . . . . . . . . . : administrator4
   Primary Dns Suffix  . . . . . . . : test.co.uk
   Node Type . . . . . . . . . . . . : Hybrid
   IP Routing Enabled. . . . . . . . : No
   WINS Proxy Enabled. . . . . . . . : No
   DNS Suffix Search List. . . . . . : test.co.uk

Ethernet adapter Local Area Connection:

   Connection-specific DNS Suffix  . : wiseman.co.uk
   Description . . . . . . . . . . . : Realtek PCIe GBE Family Controller
   Physical Address. . . . . . . . . : FC-AA-14-67-F7-C9
   DHCP Enabled. . . . . . . . . . . : Yes
   Autoconfiguration Enabled . . . . : Yes
   Link-local IPv6 Address . . . . . : fe80::98a9:8b41:f4e7:6fba%12(Preferred)
   IPv4 Address. . . . . . . . . . . : 192.168.2.25(Preferred)
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Lease Obtained. . . . . . . . . . : 25 April 2016 11:44:18
   Lease Expires . . . . . . . . . . : 03 May 2016 11:44:18
   Default Gateway . . . . . . . . . : 192.168.2.254
   DHCP Server . . . . . . . . . . . : 192.168.2.220
   DHCPv6 IAID . . . . . . . . . . . : 318548500
   DHCPv6 Client DUID. . . . . . . . : 00-01-00-01-1E-38-7D-E2-FC-AA-14-67-F7-C9

   DNS Servers . . . . . . . . . . . : 192.168.2.220
                                       192.168.2.221
                                       192.168.3.222
   NetBIOS over Tcpip. . . . . . . . : Enabled

Any Ideas?
The renew will have problems - because it can't renew with a server that no longer exists.

If you shut the old server down and then do an IPCONFIG /RELEASE on a client, THEN renew, what happens then?
Ok so I shutdown the old server then release - created new scope on new server but not overlapping ip range and I still have the same problem -  the client won't pickup ip numbers from new dhcp server - its as if the client will only respond to the old server. Is there not a way to release it from the old server altogether? Or force it to use a certain DHCP server ?

Ian.
You did an ipconfig /release on the client after shutting down the old server?  Any errors on the ipconfig /release?

Did you verify the new server is authorized and the scope is active?  Can we see a screen shot of your DHCP console with everything expanded?  

Did you try any other machines that might not have a current lease on the old server to see if they can get an address?
Yep after shutting old server down and no messages (Actually I stopped the DHCP service, I didn't actually shut it off)

Yep new server has been authorized and the scope is active screen shot below.

Thanks for you help on this any other ideas?

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Ok, now for the dumb questions.  My apologies. . .

Did anything already grab the 5 ips you setup in DHCP?

Is anything pingable on those IPs and thus not allowing DHCP to give them out?

Did you try another client (Hopefully one that's been offline for a while?)
Nope nothing grabbed the 5 IP addresses - all 5 addresses are complete free - another client hmm no not yet I'll try it tomorrow

thanks for you help today
Have you released the old IP with an ipconfig /release ?
And then an ipconfig /renew ?
Yes vivgatt - Stopped the DHCP service on old server and the ipconfig /release on client

New server is running DHCP already so ipconfig /renew and it just sits there eventually come up with a time out error.

The only thing I am wondering about now is the fact that effectively I've have two authorised and active scopes on my network.
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Basic tests first :
Can you ping the clients from the DHCP server (or the contrary) when the client has a static IP address ?

If your clients and DHCP server are not on the same subnet, have you created a DHCP-RELAY (ip helper address) on the routing device (switch or router) ?
We only have one sub-net and yet they can ping each other
Can you check the dhcp logs on the new server?

If you can also run a packet analyzer on the DHCP server (wireshark and/or MS Netmon), filtering on DHCP (udp 67 and udp 68), you may have some clues:
The client should send their DHCPDISCOVER on the broadcast address, so the DHCP server should receive it, and it should answer.
Yep i'll do that tomorrow and feed back...