TheAppWebServerHangsORDevRandomHangs < DULG

%SECTION0{name=TheAppWebServerHangsORDevrandomHangs}% The =appWeb= server hangs *OR* /dev/random hangs

   Question:: I try to run the =appWeb= server, but it hangs,
      because read accesses to =/dev/random= hang forever. What's wrong?

   Answer:: Your configuration of the Linux kernel does not contain drivers
      that feed enough entropy for =/dev/random=. Often mouse or keyboard drivers
      are used for this purpose, so on an embedded system without such devices
      =/dev/random= may not provide enough random numbers for your application.

   Workaround:: As a quick workaround you can use =/dev/urandom= instead; i. e.
      try the following commands on your system:
      <verbatim>
   # cd /dev
   # rm -f random
   # ln -s urandom random
      </verbatim>

   Solution:: The correct solution for the problem is of course to feed
      sufficient entropy into =/dev/random=. To do so you can modify
      one or more appropriate device drivers on your system;
      for example if you know that there is sufficient traffic on
      network or on a serial port than adding =SA_SAMPLE_RANDOM= to
      the 3rd argument when calling the =request_irq()= function in your
      ethernet and/or serial driver(s) will cause the
      inter-interrupt times to be used to build up entropy for
      =/dev/random=.

14.3.28. How can I access U-Boot environment variables in Linux?		1. Abstract		14.3.30. Swapping over NFS
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