Question : Microsoft tool to check for correct opened ports for AD

Hi,

I know that the following articles devine what ports are required for an open AD between servers, but from memory I once used a tool from Microosft that checked connectivity between DCs to see if any ports were being blocked that should not be blocked.

http://support.microsoft.com/default.aspx/kb/832017
http://support.microsoft.com/kb/179442

I have a private VPN provided by a service provider and on some sites I have DCs loosing connectivity to the domain.  Only a dcpromo /forceremoval and killing the DC from AD then a DCpromo will resolve it.  I am thinking that the service provider may have a filter on something that may cause this issue over a long period of time and I want to find the MS tool so I can check this out.

Can someone point me to the MS tool?

PS

Answer : Microsoft tool to check for correct opened ports for AD

Portqry is the tool we use for this, really great tool to check ports.  Then if the provider is telling you they are open you can show them that they are not

http://support.microsoft.com/default.aspx/kb/310456

How to Use Portqry to Troubleshoot Active Directory Connectivity Issues

Another set of tools that can be helpful are netmon and/or wireshark.  Packet captures with those tools can also really help you figure out what is going on.

Thanks

Mike