Cryptography is a voracious consumer of randomness, and computers depend on cryptography for security. Most operating systems harvest this randomness (under the name of entropy) from various pieces of hardware, quite often from mouse movement or keyboard operation. This is fine when the computer has a keyboard and/or mouse, but what happens when the computer is running headless?Raspberry Pis quite often run headless, and remote operation using products like RealVNC encrypt the communication between the server and the client. To maintain security, no connection can be made until there is sufficient stored entropy. This can lead to long delays between switching the computer on and being able to connect to it remotely.
The package haveged is available in Debian based systems (including Raspbian and Ubuntu) and fills the entropy pool when the supply falls below a set value. This will speed up the start up of RealVNC.
Installing haveged
sudo apt-get install haveged
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