Hello Anthony,
Hope you have a lovely day !
To address the issue of configuring DNSv6 on a DHCP Server Scope on Windows Server 2019, it appears there's a misunderstanding or misconfiguration concerning the DHCPv6 options. The DNS server addresses FEC0:0:0:FFFF::1 to ::3
you are seeing are part of the Site Local addresses which are deprecated and shouldn’t be used for DNS configuration. Instead, you should ensure that you're setting the correct DHCPv6 option for DNS servers, which is Option 23 (DNS Recursive Name Server).
Here's a step-by-step guide to correctly configure this:
Step 1: Verify DHCPv6 Scope Configuration
First, ensure that your DHCPv6 scope is correctly set up and that the server is authorized and active.
Step 2: Set the Correct Option for DNSv6
The standard option for DNS servers in DHCPv6 is Option 23. Here’s how to set it:
1. Open the DHCP Console: Go to `Server Manager` > `Tools` > `DHCP`.
2. Navigate to your DHCPv6 Scope: Expand your server name, then navigate to `IPv6` and further to the specific scope you have configured.
3. Right-click the Scope: Choose `Properties`.
4. Go to DNS Tab: Ensure that `Enable DNS dynamic updates according to the settings below` is checked and appropriately configured.
5. Set the DNS Servers: In the scope’s properties window, you might need to go to a different tab such as `IPv6 DNS Servers` to specifically configure the DNS addresses. This might not be as straightforward as in IPv4 settings, so ensure to check under all tabs.
Step 3: Configure Option 23
If directly setting via the GUI does not work or you need to verify the command line:
1. Open PowerShell or Command Prompt as Administrator.
2. Use the following commands to add the DNS server addresses to your DHCP scope:
netsh dhcp server v6 scope <scopeID> set optionvalue 23 IP6ADDRESS <IPv6 DNS Server 1>
netsh dhcp server v6 scope <scopeID> set optionvalue 23 IP6ADDRESS <IPv6 DNS Server 2> add
Replace `<scopeID>` with your specific scope identifier and `<IPv6 DNS Server 1>` with the actual IPv6 DNS server addresses you wish to use.
Step 4: Restart DHCP Service
After applying the changes, restart the DHCP service to ensure all configurations are applied correctly:
Restart-Service -Name DHCPServer
Step 5: Verify on Client Machine
On a client machine, after ensuring it is set to receive IPv6 addresses and DNS information via DHCP:
1. Release and Renew DHCP Lease:
ipconfig /release6
ipconfig /renew6
2. Check Configuration:
ipconfig /all
Look for the DNS servers under the IPv6 configuration to verify that the correct settings have been applied.
If the problem persists, ensure there are no policies or firewall settings on either the server or client that might be blocking DHCPv6 options. Additionally, check any other DHCPv6 servers in the network to ensure there are no conflicts or overrides.
Best regards
Rosy
