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SAVE-ENTROPY(8) 	     System Manager's Manual		 SAVE-ENTROPY(8)

NAME
     save-entropy -- Save bits of entropy to feed /dev/random at startup

SYNOPSIS
     save-entropy

DESCRIPTION
     The  save-entropy	command is used to save entropy data from /dev/random to
     files in a specified output location.  The files saved are used at  startup
     to  provide  additional  entropy  for /dev/random.  The output file will be
     different in every invocation until the maximum number of	different  files
     is reached.  (See entropy_save_num for details).  By default this script is
     invoked via cron(8) every eleven minutes approximately.

     This command does nothing if executed inside a jail(8).

     Three variables in /etc/rc.conf regulate the behavior of the script:

     entropy_dir
	     Specify  the  directory  for  saved  entropy  files.   Defaults  to
	     /var/db/entropy.  If set to "NO" it disables  caching  entropy  via
	     cron(8).  This setting is shared with /etc/rc.d/random.

     entropy_save_sz
	     Size of the entropy cache files.  Defaults to 4096.

     entropy_save_num
	     Number of entropy cache files to save.  Defaults to 8.

FILES
     /etc/rc.conf

EXIT STATUS
     The  save-entropy	utility  exits	0 on success, and >0 if an error occurs.
     Errors will be recorded in the system log.

SEE ALSO
     syslog(3), random(4), rc.conf(5), cron(8)

HISTORY
     The save-entropy command first appeared in FreeBSD 5.0.

AUTHORS
     The  save-entropy	command  was   originally   written   by   Doug   Barton
     <dougb@FreeBSD.org>.  This manual page was written by
     Fernando Apesteguia <fernape@FreeBSD.org>.

FreeBSD ports 15.1	       September 18, 2023		 SAVE-ENTROPY(8)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=save-entropy&sektion=8&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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