Setting up server entropy using Haveged

The Linux pseudo random number generator (PRNG) is a special device that generates randomness from hardware interrupts (keyboard, mouse, disk/network I/O) and other operating system sources. This randomness is used mostly for encryption like SSL/TLS, but also has many other uses.

When this randomness is used up, you will encounter massive delays in the start and run time of flex.bi and other programs on your server, that's why we recommend using haveged.

Installing Haveged

To install Haveged on a Centos 8 OS, follow these instructions:

1. Add EPEL repository to your server following this instruction

2. Then install Haveged and start it:

   sudo dnf install haveged
   systemctl enable haveged
   systemctl start haveged

3. To test the amount of available entropy, you can run the following command:

   cat /proc/sys/kernel/random/entropy_avail