1. Syslogsangjung.woo@gmail.com

2. Syslog Standardfor logging program messages Generating log from both kernel and app Storing log into files, named pipes, remote hosts and specific users Both of them printk/klog for kernel event syslogd for app event

3. Syslog usage Java App 1 Java App 2 Music Video Player Multimedia FW JVM Kernel - Critical Message - Warning - Information - *(Everything) - Critical Message - Warning - Information

4. Syslog configuration Syslogd default conf file /etc/syslog.conf Selector + Action Sector: Facility + Priority Action: Write destination

5. Syslog configuration – con’d Priority (/usr/include/sys/syslog.h) emerg alert crit err warning notice Info debug

6. Syslog configuration – con’d Predefined facility (/usr/include/sys/syslog.h) kern mail deamon auth news ftp user0~user7

7. Syslogd Restart syslog daemon sudo /etc/init.d/sysklogdrestart /etc/init.d/sysklogd status

8. Example Modify syslog.conf User level code

9. Example – con’d Log message

10. Extension Syslog configuration local3.err local3.* local3.3 (error) local3.err; local3.crit *.debug

11. printk

12. Tip

13. Utility logrotate Circular logging, compress and remove Send email using crontab logger Command line syslog tool logger -p local0.err 'this message is sent using command line'

14. Remote logging Modify syslogd script on receiver SYSLOGD="${SYSLOGD} -m 0 -r“ Modify syslog.conf on sender local0.* @your.host.name