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Is there anything I can do to ensure they're not putting out the same addresses? It sounds like they don't communicate like I assumed.
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Is there anything I can do to ensure they're not putting out the same addresses? It sounds like they don't communicate like I assumed.

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Thank you. I have a lot to learn about older OS's!
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Thank you. I have a lot to learn about older OS's!

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I relatively recently demoted one of our two 2008 domain controller, and added a 2016 DC. We'll call them DC1 (2008) and DC2 (2016).<br />
<br />
AD, DNS, DHCP (To an extent) have been fine...but I noticed today that nslookup is searching DC1 and returning &quot;Can't find...&quot;.<br />
<br />
I went into both DC's and they do not share each others DHCP leases. DC1 has some, and DC2 has the others. I've been fortunate not to have a duplicate address leased, but I'd like to get this straightened out before one is.<br />
<br />
Is there a compatibility issue between 2008 and 2016 DHCP i overlooked? I'm not able to set a failover in 2016 to anything less than a 2012 DHCP server.
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I relatively recently demoted one of our two 2008 domain controller, and added a 2016 DC. We'll call them DC1 (2008) and DC2 (2016).

AD, DNS, DHCP (To an extent) have been fine...but I noticed today that nslookup is searching DC1 and returning "Can't find...".

I went into both DC's and they do not share each others DHCP leases. DC1 has some, and DC2 has the others. I've been fortunate not to have a duplicate address leased, but I'd like to get this straightened out before one is.

Is there a compatibility issue between 2008 and 2016 DHCP i overlooked? I'm not able to set a failover in 2016 to anything less than a 2012 DHCP server.

DHCP leases not syncing between two DCs

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Active Directory

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DHCP

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Windows Server 2008

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Windows 10

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Azure

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