Whats Smon..

Well I was browsing for the Smon process i could not find much information about it.
Anyway putting it in very simple words its basically a process that must be up and running in the background in case any database instance is available.Whats interesting is that if u are using RAC than there can be many instance of the Oracle database that must be active at any instance, this is possible because of the clusters.
Hence to connect to any of the oracle databases available you must ensure that smon is running.

The simplest way to ensure this is by checking all the processes that are running at this time.This can be done by making use of ps -e command, if many processes are running we can make use of grep by pipe lining it with the ps-e out put.

Hence the command turns out to be
ps -ef |grep smon

Hence if grep gets u something means DB instance is up and running .