How to increase the entropy pool without using a keyboard or mouse?

Issue

• The system is reporting that there is not enough entropy in the pool for SSL connections and other security-related applications.
• How can I increase the entropy pool without using a keyboard or mouse?
• Does the command rngd -r /dev/urandom -o /dev/random really help to resolve the low entropy issue?
• Is it recommended to replace /dev/random with /dev/urandom in RHEL?
• Is it advisable to change /dev/random to a softlink to /dev/urandom?