diff --git a/man4/random.4 b/man4/random.4 index 251998109..4a32aacc6 100644 --- a/man4/random.4 +++ b/man4/random.4 @@ -171,7 +171,7 @@ This reduces the actual amount of noise in the entropy pool below the estimate. In order to counteract this effect, it helps to carry entropy pool information across shut-downs and start-ups. -To do this, add the following lines to an appropriate script +To do this, add the lines to an appropriate script which is run during the Linux system start-up sequence: .nf @@ -186,7 +186,8 @@ which is run during the Linux system start-up sequence: fi chmod 600 $random_seed poolfile=/proc/sys/kernel/random/poolsize - [ \-r $poolfile ] && bytes=\`cat $poolfile\` || bytes=512 + [ \-r $poolfile ] && bits=\`cat $poolfile\` || bits=4096 + bytes=$(expr $bits / 8) dd if=/dev/urandom of=$random_seed count=1 bs=$bytes .fi @@ -201,9 +202,14 @@ run during the Linux system shutdown: touch $random_seed chmod 600 $random_seed poolfile=/proc/sys/kernel/random/poolsize - [ \-r $poolfile ] && bytes=\`cat $poolfile\` || bytes=512 + [ \-r $poolfile ] && bits=\`cat $poolfile\` || bits=4096 + bytes=$(expr $bits / 8) dd if=/dev/urandom of=$random_seed count=1 bs=$bytes .fi + +In the above examples, we assume Linux 2.6.0 or later, where +.IR /proc/sys/kernel/random/poolsize +returns the size of the entropy pool in bits (see below). .SS /proc Interface The files in the directory .I /proc/sys/kernel/random