When kickstarting a CentOS 7 system, with configuring full disk encryption, the anaconda process either hangs on obtaining enough entropy or will take the entire 10 minutes (timeout period).

Is there a way to either point to the kickstart server to get enough entropy, or some other method? With unattended installations this adds lots of time to the whole process when it does work. When it doesn't it needs to be restarted to try again.



Install haveged on the server to solve the lack of entropy problem.

sudo yum install haveged

From man haveged

The HAVEGE (HArdware Volatile Entropy Gathering and Expansion) algorithum harvests the indirect effects of hardware events on hidden processor state (caches, branch predictors, memory translation tables, etc) to generate a random sequence. The effects of interrupt service on processor state are visible from userland as timing variations in program execution speed. Using a branch-rich calculation that fills the processor instruction and data cache, a high resolution timer source such as the processor time stamp counter can generate a random sequence even on an "idle" system.

In Linux, the hardware events that are the ultimate source of any random number sequence are pooled by the /dev/random device for later distribution via the device interface. The standard mechanism of harvesting randomness for the pool may not be sufficient to meet demand, especially on those systems with high needs or limited user interaction. Haveged provides a daemon to fill /dev/random whenever the supply of random bits in /dev/random falls below the low water mark of the device.

  • The issue is not with a fully running system. This problem is for a system that is being installed through PXE Boot with Full Disk Encryption. – asolak Jul 24 '17 at 10:38

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