Boot delay/issues because of limited entropy
In Alpine Linux 3.9, the booting process may be slowed down by entropy generation.
This is because RDRAND (entropy gathering that requires trusting the
CPU) is disabled by default.
This decision was made due to a lack of consensus as to whether or not
the hardware can be trusted to perform randomness generation (a
security-critical task).
It is possible to re-enable it through the kernel command line as so:
‘random.trust_cpu=on’.
If you trust the CPU manufacturer, add ‘random.trust_cpu=on’ to your
kernel command line using the configuration of your boot manager.
If you do not, but still wish to gain a faster boot speed, you may
consider haveged or similar entropy-generating daemons.
We already discussed on IRC how we could work around this issue by
detecting entropy in the installer but this would not cover users who
are upgrading.
Other ways would be to alarm the user at boot when entropy is too low
and services would be slow or fail to start.
(from redmine: issue id 9960, created on 2019-02-04, closed on 2019-05-09)
- Changesets:
- Revision e67c2f8b by Natanael Copa on 2019-04-25T12:31:17Z:
main/linux-vanilla: upgrade to 4.19.36
also enable CONFIG_RANDOM_TRUST_CPU
https://askubuntu.com/questions/1070433/will-ubuntu-enable-random-trust-cpu-in-the-kernel-and-what-would-be-the-effect/1071196#1071196
ref #9960- Revision 3dab4b17 by Natanael Copa on 2019-05-06T12:30:12Z:
main/linux-vanilla: upgrade to 4.19.36
also enable CONFIG_RANDOM_TRUST_CPU
https://askubuntu.com/questions/1070433/will-ubuntu-enable-random-trust-cpu-in-the-kernel-and-what-would-be-the-effect/1071196#1071196
fixes #9960
(cherry picked from commit e67c2f8bcb163695a5917e059a2c7ba46726ee89)