How to include systemlogs in your post when trouble shooting

Thanks to the EndeavourOS guys for writing this. I stole this fair and square.



In the majority of cases, simply describing your issue will not provide enough information for someone to identify it’s the cause and advise you on how to resolve it. It is important to include any system logs that may be relevant to your issue to ensure that neither your time nor the other person’s time is wasted. The following is a list of the most common system logs and where/how to obtain them. The logs are listed in the order of importance.

Essential : we need to be able to re-produce the issue! Thus, steps are required.


Systemd Journal:

The systemd journal can only be accessed using the journalctl command. You can export your system’s journal from the last three boots using these commands:

su journalctl -b -0 > /tmp/journal journalctl -b -1 > /tmp/journal.last journalctl -b -2 > /tmp/journal.2last exit

Now you can open the 3 files under /tmp with any text editor.

If you want them posted into the forum you can just Pastebin them:

cat /tmp/journal | curl -F 'f:1=<-' ix.io

cat /tmp/journal.last | curl -F 'f:1=<-' ix.io

cat /tmp/journal.2last | curl -F 'f:1=<-' ix.io

Learn more about the Pastebin command further down.


Xsession:

Your session log is located in your /home directory:

~/.xsession-errors ~/.xsession-errors.old


Xorg (X11):

You can find your Xorg logs here:

/var/log/Xorg.0.log /var/log/Xorg.0.log.old


Lightdm:

LightDM’s logs can be found here:

/var/log/lightdm/lightdm.log /var/log/lightdm/x-0-greeter.log


Other log providers and options:

journalctl --since "10 minutes ago"

To get the journal from timespan (works also with hours seconds, days)

After the command sends the logfile it gives out a short URL looking like this one:

http://ix.io/1Rmn

A good way to get information about a particular program:

journalctl -f /usr/bin/"Executable" 

And nice to post a Pastebin the smart way:

"command" | curl -F 'f:1=<-' ix.io

System summary and boot log example:

lspci > log.txt && lsusb >> log.txt && journalctl -b -0 >> log.txt && cat log.txt | curl -F 'f:1=<-' ix.io

Other systemd logs/analyse:

systemd-analyze blame

This will show systemd times during boot.

More information here.


Pastebinit:

install pastebinit with package manager or sudo pacman -S pastebinit

the command should be passed like this:

journalctl -b -0 > ~/journal.txt && pastebinit -i ~/journal.txt -b lpaste.net

Here you can change journalctl -b -0 with any other command like dmesg from below, his will write to a txt file: ~/journal.txt under your home you can change this name (journal) to something related to the command you pass…

pastebinit will auto-upload this to the Pastebin service you can choose (list all available by running pastebinit -l in the terminal.

This gives the link to it as output, so that you can just copy and paste into your post.

System summary and boot-journal example:

lspci > log.txt && lsusb >> log.txt && journalctl -b -0 >> log.txt && pastebinit -i log.txt -b lpaste.net

This will give out a link (sample) which you can post to the forum, this will include all the output of:

  • lspci (list your pci devices)
  • lsusb (same for USB)
  • dmesg (bootup messages) and make it available.

Hardware Information Systems:

INXI: smxi.org

inxi -Fxxc0

Or to autopastebin it and get an URL to post:

inxi -Fxxc0 | curl -F 'f:1=<-' ix.io

Final Note:

Very important! Do not paste only the printed contents of the command.

Always show also the command you used to get that output .

And better to use an external Pastebin if the output is very large because it is hard to get the overall question visible, inside your post, or for the discussion, if it is interrupted by large logs!

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