Windows Server 2008 and later use the IANA range which uses the ports between 49152 and 65535 providing 16,383 ports.

you can use the script mentioned in below link to detect if this is happening.

http://blogs.technet.com/b/clinth/archive/2013/08/09/detecting-ephemeral-port-exhaustion.aspx

you can use Netstat -ano to find which process is consuming all the ports, In our case it was rtcsrv(lync) process.

Use below command to see what all dynamic ports are allocated to the machine:

netsh int ipv4 show dynamicport tcp

Capture

To allocate more ports, which we have done as of now below is the example:

netsh int ipv4 set dynamicport tcp start=30000 num=35535

Now run the first command again you will see that there is more allocation now.

Capture1

After increasing the ports We were able to access domain shares which proves that ports exhaustion was the issue ..

We are still working on if there is any issue, on why ports are getting exhausted or this is normal in our case because of usage has increased . Lets see what comes out..:)

Regards

Sukhija Vikas

http://msexchange.me