Ubuntu(Linux) Log files and usage

 

 Its really important some times to check log files whether you are working on your home system or on server etc.So lets see how we can do that in ubuntu (linux).Well this will work for most of linux distributions.First thing we must know is which log file contain what and where it is located on our system so that we can access it according to our need...

=> /var/log/messages or /var/log/syslog : General log messages
=> /var/log/boot : System boot log
=> /var/log/debug : Debugging log messages
=> /var/log/auth.log : User login and authentication logs
=> /var/log/daemon.log : Running services such as squid, ntpd and others log message to this file
=> /var/log/dmesg : Linux kernel ring buffer log
=> /var/log/dpkg.log : All binary package log includes package installation and other information
=> /var/log/faillog : User failed login log file
=> /var/log/kern.log : Kernel log file
=> /var/log/lpr.log : Printer log file
=> /var/log/mail.* : All mail server message log files
=> /var/log/mysql.* : MySQL server log file
=> /var/log/user.log : All userlevel logs
=> /var/log/xorg.0.log : X.org log file
=> /var/log/apache2/* : Apache web server log files directory
=> /var/log/lighttpd/* : Lighttpd web server log files directory
=> /var/log/fsck/* : fsck command log
=> /var/log/apport.log : Application crash report / log file

View log files using GUI tools using the GNOME System Log Viewer

System Log Viewer is a graphical, menu-driven viewer that you can use to view and monitor your system logs. System Log Viewer comes with a few functions that can help you manage your logs, including a calendar, log monitor and log statistics display. System Log Viewer is useful if you are new to system administration because it provides an easier, more user-friendly display of your logs than a text display of the log file. It is also useful for more experienced administrators, as it contains a calendar to help you locate trends and track problems, as well as a monitor to enable you to continuously monitor crucial logs.
You can start System Log Viewer in the following ways:
Click on System menu > Choose Administration > Log file viewer:

(The GNOME System Log Viewer)
Note you can start the GNOME System Log Viewer from a shell prompt, by entering the following command:
$ gnome-system-log &