So, if there is some problem with my computer, be it hardware or software, what are the major log files and where are they located?
Also, is there a generic location where log files of the other packages might be located?
So, if there is some problem with my computer, be it hardware or software, what are the major log files and where are they located?
Also, is there a generic location where log files of the other packages might be located?
All log files are located in /var/log
directory. In that directory, there are specific files for each type of logs. For example, system logs, such as kernel activities are logged in syslog
file.
Some of the most common log files in that directory is :
In directory apt
there is a file history.log
which saves all the package installation and removal information even the initial system build as Live CD. You can open this file to see this very interesting file.
In directory dist-upgrade
there is a file apt.log
which logs the information during distribution upgrades
In directory installer
the log files which are created during installation can be found.
There is an apport.log
file which saves information about crashes in your system and reporting them.
The file auth.log
includes information about the authentication activities such as when you authenticate as root user via sudo.
The file dpkg.log
saves the low level details of package installation and removal related with dpkg
. You might be aware that the apt
system depends on dpkg
for package installation and removal.
boot.log
includes information of each booting.
kern.log
saves kernel information such as warnings, errors etc.
alternatives.log
includes the history of all the alternatives set by various packages and their removal via update-alternatives
command.
Another important log file is Xorg.log
which include information about the graphics driver, its failures, warnings etc.
Some other types of Log files may be there depending on your installed packages. For example, My system also includes a log files epoptes.log
which will only be there if you install epoptes
package.
systemd
With the advent of systemd
, logging is mostly handled by journalctl
utility and store the logs in binary format in /var/lib/systemd/catalog/database
file. This file enumerates all logs including kernel, boot and application logs and provides required logs via journalctl
utility.
Here is a good article on journalctl
on how you can use it to fetch required log info.