After DCs rebooted, clients are not able to ping

Question

I was setting up ADI Jumpcloud on the DCs. The install called for reboot after installing the sync agent. Sometime after this, the DCs became undiscoverable. Cannot IP or resolve name. I can ping out to internet but not clients or DCs themselves. Please help

Answer 1

Hello,

 

Thank you for posting in Q&A forum.

Based on your description, here are some possible causes and solutions:

1. Ensure that the DC's network interface is properly configured, including the IP address, subnet mask, default gateway, and DNS server.

If the DC's IP is configured to be static, make sure that the address does not conflict with other devices on the network.

Try to access their management interface independently by connecting directly to the DC and, if you can, check your network connection.

2. Check if the DNS service on the DC is running. You can open a command prompt on your DC and type services.msc to see the status of your DNS server service.

Make sure that the DNS is configured correctly, and that the address where the DC applies DNS should be its own IP address as well as other reliable DNS servers (such as public DNS or the IP of another DC).

Use the command nslookup to test if the DNS resolution is working properly.

3. Ensure that all critical Active Directory services are running, including Active Directory Domain Services and DNS Server services. You can use services.msc or the command Get-Service to check.

If the services don't start, try starting them manually.

4. Check your firewall settings to make sure that you are not blocking local network traffic or that specific Domain Services ports (such as LDAP port 389, DNS port 53, and Kerberos port 88) are blocked.

If you have other network devices, such as firewalls or routers, verify that their settings are not affecting the reachability of the DC.

5. If the above steps still do not resolve the issue, consider booting the DC in safe mode and checking the log files (located at %SystemRoot%Debug and %SystemRoot%System32WinevtLogs) and may find an error message.
6. If possible, restart the DC and see if you can restore the network connection. Sometimes, a simple reboot may resolve a temporary problem.

Use a network monitoring tool to inspect the DC's network traffic to ensure that it is not in network isolation.

 

I hope the information above is helpful.

If you have any questions or concerns, please feel free to let us know.

 

Best regards，

Jill Zhou

 

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Answer 2

Thnx for the info... all checked out fine. Of course the one thing I failed to check was restart changed the network profile to public.

Restart "Network Location Awareness" aka "NlaSvc" fixed the issue. Thnx