I am trying to move a DHCP range froma Win 2K svr to a Win 2K3 Svr. I have unauthorized the scope, than deleted the scope, and than removed DHCP (Add/Remove Windows components) from the Wind 2k Svr. When I go to add the range to the Win 2k3 Svr, I ge this message "The address range and mask conflict with an existing range." Can anyone tell me how ot reslove this issue. I have replicated to all DCs from the Win2K Svr.
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Move DHCP range
- Thread starter konopj
- Start date
WhoKilledKenny
MIS
How many scopes do you have configured on your new DHCP server? Check all the subnet masks in each scope for a typo. DHCP will not allow you to created different Scopes that overlap each other, it will not allow two different scopes to give out the same address within the same subnet.
- Thread starter
- #3
This was a fully functional DHCP on the old server. The new server currently has another scope runningon it. This would be the 2nd scope added to this server. I have tried adding this scope to another server adn I get the same message. It is liek AD is holding on to some information.
WhoKilledKenny
MIS
Did you Unauthorize the old DHCP Server or Remove it?
- Thread starter
- #5
WhoKilledKenny
MIS
I don't know if this would cause the problem, but did you check your DNS servers to see if the Service Records for your old DHCP server have been removed?
- Thread starter
- #7
WhoKilledKenny
MIS
Nevermind about the service record as I don't see one in my DNS server for DHCP. I was under the assumption that there would be one. But now that I think of it, the client sends a broadcast which explains why it would not query DNS for a DHCP server.
To help assist in troubleshooting could you provide the configuration of your scope?
To help assist in troubleshooting could you provide the configuration of your scope?
- Thread starter
- #9
WhoKilledKenny
MIS
Ok I need the subnet mask as well to determine the Network and Host portion of your IP range.
- Thread starter
- #11
WhoKilledKenny
MIS
Ok, so with the subnet mask you provided, the network portion is 10.5.80.x thru 10.5.95.x - Which means that if you have another scope on DHCP that is setup with any network portion within this range, you will get the error you are receiving. For example if you have a scope set up - say 10.5.81.x thru 10.5.82.x - You will have an overlap when trying to build the scope you described above, as they are the same network.
I will not ask why you have subnetted your network in this fashion, as Im sure you have a reason. Here are a couple of suggetstions to look at.
1. When createing your DHCP Scope, I would create it as 10.5.80.2 10.5.95.254 - This way the complete network range is part of the DHCP scope. Then you can create exclusions for any part of the Network that is to be managed for devices that require static IP and/or Reservations.
2. Another thing I would check on is... is the old scope on the old DHCP server a regular or a Super Scope?
Hope this information helps...
I will not ask why you have subnetted your network in this fashion, as Im sure you have a reason. Here are a couple of suggetstions to look at.
1. When createing your DHCP Scope, I would create it as 10.5.80.2 10.5.95.254 - This way the complete network range is part of the DHCP scope. Then you can create exclusions for any part of the Network that is to be managed for devices that require static IP and/or Reservations.
2. Another thing I would check on is... is the old scope on the old DHCP server a regular or a Super Scope?
Hope this information helps...
- Thread starter
- #13
We have the 10.5.80.0-10.5.89.254 assigned to us from corperate office all 20 bit masks. We do have 2 other snaller scopes set up on 2 different DC for redundancy. I just retired the form DC that contained this scope today and still can not create the new scope. THe only thign that I can thinko fis that there were a handfull of leases left that I deleted after the scope was upauthorized adn delted adn the lease was for 7 days. Those leases would be set to expire on 9/4/06. All that I can thinkis that somthign is holding on to that date and when that tiem comes I will be abel to reclaim that scope.
WhoKilledKenny
MIS
The current lease would not be a problem. The clients that have a lease will try to contact the old DHCP to renew when the lease time is at 50%(in your case 3.5 days). Since they won't be able to contact the old DHCP server they will continue to hold the lease until something like 77% of the lease time, if they still can't contact the old DHCP server they will try to get a new lease from another DHCP. At 100% of the lease if they can't renew the lease from the old or a new, the client is dead in the water.
Placing New DHCP server on the Network for the subnet would renew those leases with the clients. You would get a few bad address entries and the new DHCP server check the availablilty of the IP before it leases one. In this instance you would just clear the bad IP until it becomes available.
I am not sure of what you mean by 2 different DC for redundancy? are you shortening DHCP to DC or are you talking about Domain Controllers? At this time a Domain Controller have nothing to do with what we are talking about, so please be clear...
What are the Configurations for the two smaller scopes that you mentioned?
Placing New DHCP server on the Network for the subnet would renew those leases with the clients. You would get a few bad address entries and the new DHCP server check the availablilty of the IP before it leases one. In this instance you would just clear the bad IP until it becomes available.
I am not sure of what you mean by 2 different DC for redundancy? are you shortening DHCP to DC or are you talking about Domain Controllers? At this time a Domain Controller have nothing to do with what we are talking about, so please be clear...
What are the Configurations for the two smaller scopes that you mentioned?
WhoKilledKenny
MIS
Sorry for the typos in the last post...
Another thought is that if corporate has assigned you 10.5.80.x/20 thru 10.5.89.x/20 then your DHCP server should have only one scope on it. If you have more than one scope, your configuration is wrong. For redundancy you can configure the same scope on another DHCP server. I will show you a high level example of how I would do this with a 50/50 split scope.
DHCPServer1
Scope:
Start IP address: 10.5.80.1 - End IP address: 10.5.89.254
Subnet mask: 255.255.240.0
Scope Options: (example only)
003 Router - 10.5.80.1
006 DNS Server - 10.5.22.22
015 DNS Domain Name - yourdomain.com
IP excluded from distribution: (So that DHCP1 does not give out IP on the DHCP2 Scope
10.5.85.0 to 10.5.89.254
DHCPServer2
Scope:
Start IP address: 10.5.80.1 - End IP Address: 10.5.89.254
Subnet mask: 255.225.240.0
Scope Options: (example only)
003 Router - 10.5.80.1
006 DNS Server - 10.5.22.22
015 DNS Domain Name - yourdomain.com
IP excluded from distribution: (So that DHCP2 does not give out IP on the DHCP1 Scope
10.5.80.1 to 10.5.84.255
Another thought is that if corporate has assigned you 10.5.80.x/20 thru 10.5.89.x/20 then your DHCP server should have only one scope on it. If you have more than one scope, your configuration is wrong. For redundancy you can configure the same scope on another DHCP server. I will show you a high level example of how I would do this with a 50/50 split scope.
DHCPServer1
Scope:
Start IP address: 10.5.80.1 - End IP address: 10.5.89.254
Subnet mask: 255.255.240.0
Scope Options: (example only)
003 Router - 10.5.80.1
006 DNS Server - 10.5.22.22
015 DNS Domain Name - yourdomain.com
IP excluded from distribution: (So that DHCP1 does not give out IP on the DHCP2 Scope
10.5.85.0 to 10.5.89.254
DHCPServer2
Scope:
Start IP address: 10.5.80.1 - End IP Address: 10.5.89.254
Subnet mask: 255.225.240.0
Scope Options: (example only)
003 Router - 10.5.80.1
006 DNS Server - 10.5.22.22
015 DNS Domain Name - yourdomain.com
IP excluded from distribution: (So that DHCP2 does not give out IP on the DHCP1 Scope
10.5.80.1 to 10.5.84.255
- Thread starter
- #16
By DC, I ment Domain controllers. And yes, I have another scopes @ 10.5.87.x. Am I better off to have big scope 10.5.85-89 or so and just just elcude the 1st 1/2 for 1 DC and the 2nd half for the other? By you last post it seems like that is what you are reccomending.
WhoKilledKenny
MIS
Yes that is what I am recomending. Like I stated a couple of posts ago. 10.5.80.x - thru - 10.5.95.x is one subnet(network), the 20-bit mask is what defines this. On that one network, you can have 4094 hosts(devices). Each scope on a DCHP server services a single subnet(network). You can't create two scopes on single DHCP server, servicing one Network. This is why you are getting the error.
I would imagine that your network team can verify this recommendation, as they were the ones who assigned the IP block and mask.
Hope this helps, and good luck...
I would imagine that your network team can verify this recommendation, as they were the ones who assigned the IP block and mask.
Hope this helps, and good luck...
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