Linux Startup Process and related configuration files

The file systems used during linux Startup and related configuration files are inconsistent between non-release versions of linux. As a result, some related configuration files involved in linux Startup are also different, it is easy to cause confusion. It is mainly reflected in the linux init process Startup Process: The related configuration files under Red Hat are:/etc/inittab/etc/rc. d/rc. sysinit/etc/rc. d/rcX. d/The symbolic links in the directory/etc/rc. d/init. d/The actual daemon script/etc/rc in the directory. d/rc. the configuration file corresponding to the local user-defined STARTUP script Ubuntu is:/etc/inittab (some do not seem to have this file)/etc/rcS. d/startup service Symbolic Link/etc/rcX. d/The startup directory corresponding to each running level, X: 0-6/etc/init. d/actual service startup script/etc/rc. the local User-Defined STARTUP script mainly sorts out the association between configuration files in the Ubuntu system: The init process reads the inittab file and starts the rcS. all services under the d directory, determine the startup running level (initdefault), and stop [K ] Or start [S] corresponding to the running level rcX. d/service rcS in the directory. d/rcX. all files in the d directory are init. d. the symbolic link of the Service script under the directory. Use the [K] identifier to indicate the stop and the [S] identifier to indicate the start. three files:/etc/init. d/rc/etc/init. d/rc. local/etc/init. the d/rcSrc script uses the first parameter to determine the specific service running directory/level, for example, rc S executes the rcS. d/services, rc 5 executes services under rc5.d. Rc. the local script runs or stops/etc/rc according to the identity. local script (if any). The default value is/etc/rc. there is no content in the local file, or there is an exit 0; you can add a custom Startup Program in it. Execute all services in the RFM. d/: exec/etc/init. d/rc S.