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I have the same DHCP scope exist in two domains. Both contain leases of client PCs. I want to have only one of the Domains will be going.

In some cases the same IP address exists in both scopes. in others the IP address may exist in one scope or the other.

What would be the impact of Deactivating and/or Deleting of one of the scopes?

Thanks

SwitchArt
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Well, that depends on how these two domains are connected. Are these DHCP servers on the same subnet? If they are, that needs to stop. You may only have one active DHCP server in any given broadcast domain (though you may use a passive failover).

Secondly, this is a bad IP scheme if these are separate networks. While it is not technically wrong to create two networks with the same subnet within an organizations private space, it will cause management and documentation problems very easily. Best create separate networks and subnets when separating broadcast domains via VLANs or similar, even if they will never touch.

Spooler
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  • DHCP servers are on separate subnets. Yep, agree, bad design, management and documentation problems - thus the reason I'm wanting to remove one. Just wanting to know the impact to end users if they suddenly lose the DHCP server that handed out their IP Address. Thanks – SwitchArt Oct 17 '16 at 03:30
  • Just turning off a scope will make that network unjoinable by DHCP enabled machines. This will only affect machines that are new to the network, or that are renewing their DHCP leases. Since you'd be creating a new network and scope (since you have to replace it with SOMETHING), you would have to make sure all of the machines got this new subnet. That would involve broadcasting a DHCP renew across your network, triggering all machines to update their IP stack with new information. – Spooler Oct 17 '16 at 03:35
  • `You may only have one active DHCP server in any given broadcast domain (though you may use a passive failover).` - That statement isn't technically correct. It's perfectly acceptable two have more than one active DHCP server on the same physical segment. High Availability and Load Balancing DHCP implementations use multiple DHCP servers per segment. Depending on the HA/LB method in use, multiple DHCP servers may be active at the same time. Split Scope DHCP is just one of these methods where multiple DHCP servers are active on the same segment. – joeqwerty Oct 17 '16 at 04:40
  • Even if we preclude an HA/LB scenario, there's nothing technically preventing you from having multiple active DHCP servers per segment. I have two independent active DHCP servers on my home network. I've manually split a range of ip addresses between these two active DHCP servers and they both serve DHCP clients with no issues. – joeqwerty Oct 17 '16 at 04:45