CPANEL USER SHELL ACCESS : FORK: RESOURCE TEMPORARILY UNAVAILABLE

Today one of the cPanel user shell access gives error as follows:

su - user
-bash: fork: Resource temporarily unavailable

The error occurs due to  cPanel and its “Shell Fork Bomb Protection”.

To fix this issue,

Logging into WHM

Go to Security >> Security Center

Shell Fork Bomb Protection and click on “Disable Protection”

It will resolve the issue.

Shell Fork bomb Protection will prevent users with terminal access (ssh/telnet) from using up the server’s resources and possibly crashing the server.