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In my new job, since a couple of months ago, the ISA 2006 server stops accepting VPN connections.

Once that happens, we restart it, and it all goes back to normal... for the next 12 hours or so.

I couldn't quite figure out how or why this was happening.

A consultant was stumped with the problem as well.

Yesterday I spent a lot of time just clicking everywhere on the ISA server...

And I think I might have found the problem.

I'm a n00b at this, so please bare with me:

I went to Administrative Tools

--> Routing and Remote Access

--> expanded de ISA server

--> expanded IP Routing

--> clicked on General

--> right click on top of "Internal", which is listed under Interface

Interface: Internal

Type: Internal

IP Address:

Administrative Status: Up

Operational Status: Connected

Incoming bytes: 0

Once I right-clicked on Internal, I selected Show TCP Connections.

And there I think is where the problem lies.

I listed everything by "State", and ended up with CLOSE_WAIT on top.

The ports are... running out fast.

When the VPN connection stops working, I check this, and amongst the highest listed ports are 64,5xx

When I reboot the server, the ports start over at the 6,xxx range.

Yet the guy climbs through 1,000 ports in a matter of 5 minutes.

Is this normal?

Is there a way to "release" the ports?

Anything I can check or verify?

Thank you very much for your help... very much appreciated.

Let me know if you would like some additional information in order to help me fix this.

Thank you!

share|improve this question
Additional info: Just checked on ISA, and somehow she restarted all the ports. She went back to ports 5,xxx. Had never seen that. –  user49399 Apr 5 '12 at 19:34
The ports typically loop. If all 60,000 high ports were used all the time, yes, this'd be a problem. But as I think you've found, it's probably not that. –  TristanK Apr 6 '12 at 2:02
Other suggestions: ensure you're patched up on Windows and ISA. –  TristanK Apr 6 '12 at 2:02

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