How to resolve issues related to Errors: 1) connection limit (1) exceeded 2) Too Many Open files error & 3) native OutOfMemory ?

Problem Definition:-
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Usually these type of errors will be seen in WebLogic, WebSphere, Tomcat logs due to Unix resource exhaustion ie. when soft limit of the open file descriptor crossed the specified limit value.

Before increasing the open file descriptor limit just check is there any process holding lock for deleted log files by using lsof command. 

Solution-1) Increase the open file descriptor value temporarily at user session level.

Example: 

ulimit -n    #command for checking current value of file descriptor 

ulimit -n  8192  # Command for increasing file descriptor value

Solution-2) Increase the file descriptor limit using WebLogic commEnv.sh upto 12.1.3 OR commBaseEnv.sh from 12.2.1.1.0 on wards.

Change from 4096 to higher value

 

Similar to below

 

Solution-3) Change the soft limit of file descriptor using /etc/security/limits.conf

Current value: 4096 for wlsuser

login to root user & Add OR update /etc/security/limits.conf with below content at the end of file.Save & Close the file.

wlsuser soft nproc 2047

wlsuser hard nproc 16384

wlsuser soft nofile 8192

wlsuser hard nofile 65536

Now login to wlsuser & check the value of file descriptor