Flashnux

GNU/Linux man pages

Livre :
Expressions régulières,
Syntaxe et mise en oeuvre :

ISBN : 978-2-7460-9712-4
EAN : 9782746097124
(Editions ENI)

GNU/Linux

CentOS 4.8

i386

rngd(8)


RNGD

RNGD

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
AUTHORS

NAME

rngd − Check and feed random data from hardware device to kernel random device

SYNOPSIS

rngd [−b, −−background] [−f, −−foreground] [−o, −−random-device=file] [−r, −−rng-device=file] [−s, −−random-step=nnn] [−W, −−fill-watermark=nnn] [−t, −−timeout=nnn] [−?, −−help] [−V, −−version]

DESCRIPTION

This daemon feeds data from a random number generator to the kernel’s random number entropy pool, after first checking the data to ensure that it is properly random.

The −f or −−foreground options can be used to tell rngd to avoid forking on startup. This is typically used for debugging. The −f or −−foreground options, which fork and put rngd into the background automatically, are the default.

The −r or −−rng-device options can be used to select an alternate source of input, besides the default /dev/hwrandom. The −o or −−random-device options can be used to select an alternate entropy output device, besides the default /dev/random. Note that this device must support the Linux kernel /dev/random ioctl API.

FIXME: document random-step and timeout

OPTIONS

−b, −−background

Become a daemon (default)

−f, −−foreground

Do not fork and become a daemon

−o file, −−random-device=file

Kernel device used for random number output (default: /dev/random)

−r file, −−rng-device=file

Kernel device used for random number input (default: /dev/hwrandom)

−s nnn, −−random-step=nnn

Number of bytes written to random-device at a time (default: 64)

−W n, −−fill−watermark=nnn

Once we start doing it, feed entropy to random-device until at least fill-watermark bits of entropy are available in its entropy pool (default: 2048). Setting this too high will cause rngd to dominate the contents of the entropy pool. Low values will hurt system performance during entropy starves. Do not set fill-watermark above the size of the entropy pool (usually 4096 bits).

−t nnn, −−timeout=nnn

Interval written to random-device when the entropy pool is full, in seconds, or 0 to disable (default: 60)

−?, −−help

Give a short summary of all program options.

−V, −−version

Print program version

AUTHORS

Philipp Rumpf
Jeff Garzik − jgarzik@pobox.com
Matt Sottek



rngd(8)