Mount | Rng Script
#!/bin/bash # mount_rng.sh — Bind hardware entropy to /dev/random if [ ! -c /dev/hwrng ]; then echo "No hardware RNG found." exit 1 fi rngd -r /dev/hwrng -o /dev/random --fill-watermark=2048
But the true mount RNG script—the one whispered in IRC channels—does more. It sanity-checks the source (FIPS 140-2 tests), it bypasses broken RDRAND implementations, it falls back to jitter entropy, and it logs every seed to a tamper-evident audit file. mount rng script
echo "Entropy bridge established. The kernel now dreams of static." echo "Entropy bridge established
When /dev/random blocks, applications weep. gpg --gen-key stalls. ssh takes seven seconds to handshake. You check cat /proc/sys/kernel/random/entropy_avail . It reads 112 . You mutter a sysadmin curse. A hardware random number generator—an RNG—is a small silicon oracle. It might be a dedicated chip (TPM, Intel RDRAND), a USB dongle (OneRNG, ChaosKey), or even a Raspberry Pi’s noisy diode. The kernel sees it as a character device, typically /dev/hwrng . But that device does nothing on its own. It sits, unused, like a library of solutions to problems no one has asked. ssh takes seven seconds to handshake
# Advanced version: mount_rng_secure.sh HWRNG=/dev/hwrng POOL=/dev/random WATERMARK=4096 dd if=$HWRNG bs=64 count=1 2>/dev/null | rngtest -c 64 || echo "CRITICAL: RNG source failing statistical tests." exit 2 Feed with rate-limiting (don't starve the hardware) while true; do need=$(cat /proc/sys/kernel/random/entropy_avail) if [ $need -lt $WATERMARK ]; then dd if=$HWRNG bs=512 count=1 2>/dev/null | cat > $POOL fi sleep 0.1 done Why "Mount"? The term is a beautiful anthropomorphism. In Unix, mounting makes a resource visible at a path. An RNG script mounts randomness into the system’s expectant void. It says: Here, kernel. Drink from this source of quantum tremors, of thermal noise, of diode avalanche. Be unpredictable again. The Philosophical Edge There is a deeper irony. We run mount RNG scripts to make our deterministic machines non -deterministic. We crave entropy for crypto, for secure boot, for lottery drawings. Yet the script itself—a sequence of predictable instructions—remains frozen. It is a spell cast by a clockwork mage.
So if you ever find yourself SSH'd into a machine whose entropy_avail reads 42 , and whose every gpg command hangs like a paused séance—write the mount RNG script. Feed the oracle. And watch randomness flow into the deterministic dark. End of piece.
You must mount the entropy source. The "mount rng script" isn't literally mounting a filesystem. It's a ritual of redirection: feeding the hardware RNG’s output into the kernel’s entropy pool. The classic incantation lives in rng-tools :