与主机的TCP / IP连接失败。 java.net.BindException：已在使用的地址：connect Driver

Question

We deployed an application long back. It's working fine so far. Suddenly, we're getting the following error today when the application is trying to connect database. It's happening on and off. some times able to connect. most often getting below error.what would be the cause. Please suggest me. Thanks in advance.

Error:-

com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host  has failed. java.net.BindException: Address already in use: connect
Driver name=com.microsoft.sqlserver.jdbc.SQLServerDriver
com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host  has failed. java.net.BindException: Address already in use: connect

Answer 1

You've run out of local ports. You have a connection leak somewhere, or you're not using a connection pool and you should be. Check netstat -anp TCP . You will see zillions of connections in ESTABLISHED state to the same target, the MS SQL Server.

Answer 2

Address already in use implies that there are not enough ports on the local side available for creating a connection. You would see a lot of entries if you check the network stats. Assuming it is windows, for the exact way to get the listing, check the platform docs. For an understanding of the issue, you can also read:
http://khanna111.com/articles/TCPAAIU.html

Note that the top 2 figures on that page are jumbled. There is an explanation of the TIME_WAIT stage as well.

The cause, if you only have that one application doing jdbc running, then the probable cause could be that TCP connections to the database server are being created and either not closed or rate of creating and closing the connections is greater than a threshold that leads to this issue. You would need to investigate a connection pool in any case if you do not already have one. If there are other applications on the same host that deal with network traffic then you would need to take a look at those as well.