Red Hat

Hi,
Guys can any one explain me the difference between init s and init 1 in linux?

this would be very useful....

thanx in advance..

regards
Amandeep

Usually there is no difference. For Red Hat, the official documentation I found doesn't even specify "s":
F.4. SysV Init Runlevels

Did you try using Google?

There are persistent and non-persistent runlevels. Non-Persistent runlevels are only active during a short period of time while the system is changing from one state to another. On RedHat, runlevel 1 is used to bring the system down from multiuser to singleuser mode. When singleuser mode is reached, the runlevel will be S.

See also man 7 runlevel.

In general, the meaning of runlevels is not absolutely fixed. I remember an old unix style OS from Siemens, called Sinix, where runlevel 1 was used for a singleuser mode login on the console, while S gave you a root shell in single user mode on the terminal where you typed the init-command. On Linux, runlevel 5 starts the graphical desktop on the console, while on Solaris, it is used to bring down the system followed by power-off!

Thanx, this is really helpful.