Simple noob questions about boot, systemd, logs, and other things

English Install/Boot/Login
#1

Hi everyone,
When booting previous releases of oS, If I pressed any arrow key when boot I could see a nice detailed log of all the services being started (the classic OK/FAIL screen), now I can’t see anything, maybe this could be because I have an SSD and the system boots too fast in order to actually see the log but I’m not sure.

Another thing related to this is that /var/log/boot.log is not being populated anymore, the only logs I see here are from udev and plymouth, I used to see here the exact same screen from boot.
Is this related to systemd and the way that systemd stores logs?

I used to force an fsck check by creating a file /forcefsck, but I think this does not work anymore. I read somewhere that now I have to force it via kernel parameters in grub.
Now, how can I see the fsck logs at boot? or later in some log?
Does putting fsck.mode=force in the kernel parameters executes the file system check for both BTRFS and XFS?
Is oS configured to execute an fsck when something went wrong? for instance, after a power outage.

Thanks.

#2

I do not know about arrow keys, but when I want to see what is going on during boot, I press the Esc key.

#3

yes. Google journalctl and you can read up on it and its features.

Also note that you can have other logging facilities installed, so, if you wanted the old method too, install, for example, rsyslog

#4

To view the previous boot log entries

journalctl -b 1

You can view other previous boot logs by specifying/changing the number in that command (eg “2” for 2 boots ago)

You can also usefully specify various options searching the journal like

Days, or time or between two specified times
Entries related to specific systemd services
Errors, and different error levels

And, a lot more.

TSU

#5

I correct my self about the logs at boot, if I press the down arrow key, I can skip the plymouth animation and see the full boot log. The log was just displayed really fast (awesome!).

I was aware of journactl and the -b option. I just thought that the boot.log was also being populated and in the same format I see when booting.

So, now that I know about the boot logs, what about forcing an fsck at boot and seeing it’s log?

Thank you guys for your attention.

#6

I doubt many people will force an fsck on boot. Thus knowledge at hand might be a bit scarce.

#7

When booting, at the Grub menu, hit “e” key. Look for the line that begins with “linux”, hit the End key to get to the end of the line, add the parameter:

fsck.mode=force

Continue booting with the F10 key.