Equivalent command 'chkconfig' in Solaris?
 

In RedHat-Linux I can use the command 'chkconfig' to add a system service and by reboot of the machine the service will be started.

Though I've googled a solution in Solaris and it seems one can use the SMF, but couldn't get a clear unterstanding.

Can someone help?

As you already noted, chkconfig is Linux specific and not available on Solaris. "chkconfig" is quite simple so could be easily ported to Solaris but AFAIK nobody made that effort.

The alternatives are either to manually add your service using the legacy init scripts or convert the it to smf and use this framework to install/configure/enable/disable it.