What is the difference between 'init s' and 'init 1'.
I know that both will work to change the current run level to single user mode.
Is there any difference in those two commands?
"init 1" is administrative mode that runs the /etc/inittab script.
"init s" is repair mode that doesn't mount filesystem. So, /etc/inittab doesn't need to be there 
Booting to runlevel 1 causes RHEL to process the /etc/rc.d/rc.sysinit script followed a single script from rc1.d which after some basic checks and cleanup execs init S.
Booting to runlevel s (S or single) causes RHEL to just process the /etc/rc.d/rc.sysinit script. If /etc/inittab is missing or corrupt, you go directly to a root shell with no scripts processed.
Thanks fpmurphy. Appreciate your explanation.
If possible coulnd you please provide any document on this init s and init S?
If you have doc, please post them.
Thanks in advance.
The RH300 training material covers it in detail.
As of now, I dont have RH material. If possible send me some docs on that please.