You can file an issue about it and ask that it be added.

• Entropy
  • Alternative entropy sources

Not available from C2S/CIS standard.

Entropy is the measure of the random numbers available from /dev/urandom.

It is important for a secure operating system to have sufficient quantities of entropy available for various crypotographic and non-cryptographic purposes, such as:

• generation of cryptographic keys
• TCP port randomisation (NAT, outbound connection)
• TCP sequence number selection
• writing random files for testing network functionality and throughput
• overwriting hard disks prior to reuse or resale or encryption

It is generally recommended wherever entropy is used heavily to supply additional entropy sources.

Haveged was created to remedy low-entropy conditions in the Linux random device that can occur under some workloads, especially on headless servers.

# Add haveged daemon to autostart
systemctl enable haveged
# For temporary change:
echo "1024" > /proc/sys/kernel/random/write_wakeup_threshold
# For permanent change (edit /etc/rc.local):
/usr/local/sbin/haveged -w 1024

To check the status of your server’s entropy, just run the following:

cat /proc/sys/kernel/random/entropy_avail

To check the maximum limit of entropy:

cat /proc/sys/kernel/random/poolsize

• Haveged