[randomlyMember]

PROBLEM SOLVED!

1. Your modem blacklisting rule in udev still works. (I read up on that stuff and now understand.)

2. It’s not a TrueRNG bug but a Systemd/Kernel bug. Basically its systemd-udev-settle.service which tries to run but fails if you use a fake block device storage.

!!!!WARNING!!!!
>>>Don’t use my solution if you use LVM! It may damage your system!<<<
You may only use it if you use no fake block device storage OR if you use LUKS encryption.

Solution: Masking this service.
systemctl mask systemd-udev-settle

Thanks to everyone who helped me along the way. I learned a lot in the process.

• This reply was modified 8 years, 10 months ago by  randomly.

[randomlyMember]

Do you have the modem-manager package installed by chance?

I’m very sorry for my late reply. I will be more responsive now!

To answer your question: I don’t have a package named “modem-manager” installed but I have one installed called “modemmanager” (D-Bus service for managing modems).

Maybe this little missing “-” is the reason why modem isn’t correctly blocked by udev rules?

[randomlyMember]

Ok, I now can fully reproduce both the scenario when udev rules fail to work and when they work fine.

It fails when I normally boot the computer from being turned off.

It works when I reboot the computer without shutting it down.

I honestly have no idea how anything can be carried over from one session to another when I restart the computer but it has to or otherwise things wouldn’t happen how they do. It seems like as if the udev rules gets executed too early or needs to run twice to work or something.

I’ll continue to try and find a fix it but I must admit that from now on I fly blind and really hope somebody who knows better how udev works can find a solution.

[randomlyMember]

Thanks for looking into the matter.
I unfortunately just realized that this didn’t fix my problem for real.

I just typed in the stty-command as suggested above, checked if it worked (yes), adjusted the udev-rule, restarted and it still worked. The initialization at boot was gone and the baud rate and flags were set as they should. So I thought I fixed it.

Now after turning my pc off and on again the TRNG fell back into normal mode with low baud and the missing flags. I guess the pc keeps the settings when just restarting?!

Anyways: There seem to be at least two problems with the udev rule when used on Ubuntu 15.04 and I only fixed one of it. I’ll investigate further but in the meantime I’d be glad if somebody else could reproduce this problem.

[randomlyMember]

OK, I’ve found the error!

Because of some update from Ubuntu 14.10 to 15.04 the syntax of udev rules changed and now it doesn’t parse %k variable.

To fix the issue do the following.

Change
/bin/stty raw -echo -ixoff -F /dev/%k speed 3000000

to

/bin/stty raw -echo -ixoff -F /dev/TrueRNG speed 3000000

and everything works again.

Have fun!

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