Re: Linux messages full of `random: get_random_u32 called from`

From: Theodore Y. Ts'o
Date: Thu Apr 26 2018 - 15:25:36 EST

On Thu, Apr 26, 2018 at 08:17:34AM -0700, Sultan Alsawaf wrote:
> > Hmm, can you let the boot hang for a while? It should continue after
> > a few minutes if you wait long enough, but wait a minute or two, then
> > give it entropy so the boot can continue. Then can you use
> > "systemd-analyze blame" or "systemd-analyize critical-chain" and we
> > can see what process was trying to get randomness during the boot
> > startup and blocking waiting for the CRNG to be fully initialized.
> >
> > - Ted
> systemd-analyze blame:
> systemd-analyze critical-chain:
> dmesg:

Hmm, it looks like the multiuser startup is getting blocked on snapd:

29.060s snapd.service @1min 32.145s
ââ @1min 32.145s
ââhddtemp.service @6.512s +28ms
ââ @6.508s
ââNetworkManager-wait-online.service @2.428s +4.079s
ââNetworkManager.service @2.016s +404ms
ââdbus.service @1.869s
ââ @1.824s
ââ @1.824s
ââsnapd.socket @1.821s +1ms
ââ @1.812s
ââapparmor.service @587ms +1.224s
ââ @585ms
ââ @585ms
ââkeyboard-setup.service @235ms +346ms
ââsystemd-journald.socket @226ms
ââsystem.slice @225ms
ââ-.slice @220ms

This appears to be some kind of new package management system for

Description-en: Tool to interact with Ubuntu Core Snappy.
Install, configure, refresh and remove snap packages. Snaps are
'universal' packages that work across many different Linux systems,
enabling secure distribution of the latest apps and utilities for
cloud, servers, desktops and the internet of things.

Why it the Ubuntu package believes it needs to be fully started before
the login screen can display is unclear to me. It might be worth
using systemctl to disable snapd.serivce and see if that makes things
work better for you.

- Ted