Hardware RNG Entropy Gatherer Daemon - failed to start

[mjz]

I just completed a Centos to Rocky migration and noticed the RNG service failed to start.

The service log shows: >

Service logs

June 14, 2024

10:27 AM

rngd.service: Failed with result ‘exit-code’.

systemd

10:27 AM

rngd.service: Main process exited, code=exited, status=1/FAILURE

systemd

10:27 AM

Maybe RNG device modules are not loaded

rngd

10:27 AM

Can’t open any entropy source

rngd

10:27 AM

[jitter]: Initialization Failed

rngd

10:27 AM

[jitter]: Unable to obtain AES key, disabling JITTER source

rngd

10:26 AM

[jitter]: Initializing AES buffer

rngd

10:26 AM

[jitter]: JITTER timeout set to 5 sec

rngd

10:26 AM

[rdrand]: Initialization Failed

rngd

10:26 AM

[hwrng ]: Initialization Failed

Any suggestions? thanks

[gerry666uk]

On default Rocky 9.4, I don’t see this service at all.

[mjz]

Do I need to install it?

[stevemowbray]

I think you need to uninstall it as it seems to be something left over from your CentOS system.

[albert.mccann]

It looks like it’s part of “rng-tools”, which should be in the baseos repo, so sudo dnf install rng-tools should work.

[mjz]

I installed rng-tools (reinstalled) and I still get RNG Entropy … failed to start. Any other suggestions?

[albert.mccann]

What does cat /etc/sysconfig/rngd
and cat /usr/lib/systemd/system/rngd.service
show?

Here’s mine:
“---------------------------”
“cat /etc/sysconfig/rngd”

“# Optional arguments passed to rngd. See rngd(8) and”
“# 1252175 – allow to specify parameters to rngd in /etc/sysconfig”
“RNGD_ARGS=”–fill-watermark=0 -x pkcs11 -x nist -x qrypt -D daemon:daemon"
“--------------”
“cat /usr/lib/systemd/system/rngd.service”

“[Unit]”
“Description=Hardware RNG Entropy Gatherer Daemon”
“ConditionVirtualization=!container”
“ConditionKernelCommandLine=!fips=1”

“# The “-f” option is required for the systemd service rngd to work with Type=simple”
“[Service]”
“Type=simple”
“EnvironmentFile=/etc/sysconfig/rngd”
“ExecStart=/usr/sbin/rngd -f $RNGD_ARGS”

“[Install]”
“WantedBy=multi-user.target”
“-------------------”

Also, try this:
“/usr/sbin/rngd -l”

I get:

Entropy sources that are available but disabled
1: TPM RNG Device (tpm)
5: NIST Network Entropy Beacon (nist)
9: Qrypt quantum entropy beacon (qrypt)
Available and enabled entropy sources:
0: Hardware RNG Device (hwrng)
2: Intel RDRAND Instruction RNG (rdrand)
6: JITTER Entropy generator (jitter)
Available entropy sources that failed initalization: