Hi,
I work on several Sun servers running Solaris (SunOS 5.10). All of these are Application Servers with a propietary software running on it.
It happens that some times (not regularly/deterministic and not so often, i.e. twice a month circa) we register what I think are network problems.
I say this because the messages appearing in alarm log from AS says:
* Can't connect to NE
* AS not available
* Connection to NE time out
Also it happened that after such alarms we had a huge number of frozen TCP connection in CLOSE_WAIT. Following this the File Descriptors for the process that handle TCP connection reached the system limit of 5120 and the AS started to transmit in UDP causing the failure of transactions since the other side didn't expect UDP packets.
Now this behavior (frozen CLOSE_WAIT) is fixed with a patch from the vendor but still remains the network (?) problems causing the alarms.

So since the first time it happened I have a fixed idea in my mind: network problems (Catalyst side to be clear).
Whatever it can be (traffic switch, downlink ...) this affect the traffic (SIP) of our AS.
The only problem is that the network guys says: from our point of view it's everything fine! Always, all the times it happens the problems!

At the end of the story:
What kind of data can I collect (and HOW!?) to DEMONSTRATE that it's a problem of the network (or the AS)?
Do you know a script or tool (not traffic affecting) that can monitor the described scenario?

Thanks you very much!

Regards,
Evan