Classification of the log file
(1) the kernel and system log
This log data rsyslog unified management, according to the main feature file / etc / rsyslog. The decision to set conf record system kernel and various programs to what location information
(2) The user log
Information system for recording user login and exit the system, including user name, terminal landing, landing time, source host, the process is using the operation
(3) log
Some applications will be selected by their own independent management of a log file instead of to the rsyslog service management, the program runs the event procedure for recording the information
The log file in / var / log / lower
Common Log File and View
View the contents of the log files are stored command
/ Var / log / messages file system kernel program failure information and other important data like cat
/ Var / log / cron periodically scheduled task to generate time information such as cat
/ Var / log / dmesg boot cat during various time information, and the like
/ Var / log / maillog e-mail activity such as cat
/ Var / log / lastlog login for each user's most recent event last, lastlog, etc.
/ Var / log / secure user authentication time information related to security cat etc.
/ Var / log / wtme each user login, logout and system startup and shutdown events users, who, w
/ Var / log / btmp failed login attempts and validation error event lastb
Level log messages
English translation significance level representation and
0 EMERG (emergency) will lead to a host system unavailability
1 ALERT (warning) must immediately take steps to resolve the problem
2 CRIT (serious) more serious cases
3 ERR (error) runtime error