High amount of CLOSE_WAIT sockets in JBoss

Issue

• We see a growing number of CLOSE_WAIT sockets on JBoss at times. How can we trouble shoot?
• Getting close wait connections on Service mix server. We have observed close wait socket connections on windows server. From windows and network perspective we have found that it is an application side issue and it was closing connections. Following is the points from windows perspective:
  • CLOSE_WAIT - Indicates that the server has received the first FIN signal from the client and the connection is in the process of being closed . So this essentially means that this is a state where socket is waiting for the application to execute close() . A socket can be in CLOSE_WAIT state indefinitely until the application closes it. Faulty scenarios would be like file descriptor leak, server not being execute close() on socket leading to pile up of close_wait sockets
  • The CLOSE_WAIT status means that the other side has initiated a connection close, but the application on the local side has not yet closed the socket
  • We see that the 8081 port is running due to “JAVA.exe”. See troubleshooting-connections-stuck-in-close-wait-status and how-to-not-get-so-many-apache-close-wait-connections.
• All indicates that the application in questions has to execute close() . Is it possible for you to involve vendor and just get a quick check on socket close matter ?