java process hung at one specific port 7568

[Zeca]

Does anybody know any tool that I could use to help the application group to identify a problem with a java application that it's listening at the port #7568 on the HP UX 11.i?
When I run netstat -a and it shows 09 connections established and 01 Listen (see attachment).
Looking at this output, it looks like everything is OK but the client applications couldn't send their messages. After the process was recycled from the application group,everything went back to normal. I'd like to put something in place that would collect some additional data in order to find the root cause if the problem occur again.

[Mel Burslan · Accepted solution]

is the number of processes 9 a magic number where it locks up or did it happen to be just at this time. If 9 is the magic number, someone might have coded the application short sightedly in java.

I am not sure what you can do to trace it but, before it happens again, make sure that you have the latest (or close enough to the latest) pthreads patch applied to your system.

Make sure you have the right patches for the right version of java as every java version, they differ. you can find version relevant to you by visiting

http://www.hp.com/go/java

HTH

[Ron Kinner]

You could set up a sniffer such as etherreal to see what is going on with the packets.

http://www.ethereal.com/

Ron

[Zeca]

Ron, thank you for the sniffer address, I'll check if can help us.

Mel, This application has 18 ports opened at the server and during some tests, each port could accept a maximum of 200 connections. At the same time these 9 connections were established at the port #7568, we had a few other connections at other ports, like 6 at port #7571 and 15 at the port #7573. I'll check the java patches but I don't think that's the problem. I'm trying to find any tools that would help us to trace and find out the root cause of this problem.

[Con O'Kelly]

Hi

Not sure if it will help but you could try using lsof, this gernerally gives better information than netstat on port use etc.
Use as follows:
# lsof -i :

http://hpux.connect.org.uk/hppd/hpux/Sysadmin/lsof-4.71/

Also look at using tcpdump to trace network traffic:
http://hpux.connect.org.uk/hppd/hpux/Networking/Admin/tcpdump-3.8.1/

Cheers
Con

[Zeca]

Thread too old