1. 中華技術學院 Linux 課程 中華技術學院 Linux 課程 Chap one : Service Control 王俊城RHCE/RHCX

2. Agenda  Service management  System V-managed services  xinetd

3. Service Management  init  System V scripts  direct command  xinetd

4. Services Managed by init  Typically non-TCP/IP services  Respawn capability  Configured in /etc/inittab  init q

5. System V Service Management  /etc/rc.d/init.d/gpm start  /etc/init.d/gpm start  service gpm start

6. chkconfig  chkconfig gpm --list  /etc/rc.d/rc?.d/*gpm  chkconfig gpm on  chkconfig gpm off  chkconfig gpm --del  chkconfig gpm --add  chkconfig telnet on  /etc/xinetd.d/telnet

7. Xinetd Managed Services  xinetd  standalone itself  less-frequently needed services  host-based authentication  service statistics and logging  service IP redirection  Replaces inetd  Linked with libwrap.so  Configuration files:/etc/xinetd.conf,/etc/xinetd.d/*

8. xinetd default controls  /etc/xinetd.conf defaults{ instances = 60 instances = 60 log_type = SYSLOG authpriv log_type = SYSLOG authpriv log_on_success = HOST PID log_on_success = HOST PID log_on_failure = HOST log_on_failure = HOST cps = 25 30 cps = 25 30} includedir /etc/xinetd.d

9. xinetd service controls  /etc/xinetd.d/* service telnet { flags = REUSE flags = REUSE socket_type = stream socket_type = stream wait = no wait = no user = root user = root server = /usr/sbin/in.telnetd server = /usr/sbin/in.telnetd log_on_failure += USERID log_on_failure += USERID disable = yes disable = yes}

10. LAB1-standalone service  runlevel  init 3  chkconfig gpm on  service gpm stop (X)  init 5 (V)  chkconfig gpm off (V)  init 3 (X)  service gpm start (V)  chkconfig gpm on

11. LAB2-xinetd  runlevel  init 3  chkconfig telnet off  telnet localhost (X)  chkconfig telnet on (V)  telnet localhost (V)  chkconfig telnet --list