Hi,
Where do i post Oracle DB related questions??
I basically have 2 questions -
What is pmon and smon? Difference between them? If either or both process fail then how can we monitor them?
Is lsnrctl same as tnslsnr? if i want to check for listener status then how would i do that?
lsnrctl status
will give me the status
but is grepping tnslsnr same as the above?
After a quick google...
pmon is a process monitor for Oracle that wakes up every few seconds and does housekeeping on certain processes, killing orphaned user processes, etc.
smon is a system monitor for Oracle that wakes up every 5 minutes and performs other housekeeping tasks, instance recovery, cleans up after a dirty shutdown, etc.
tnslsnr is the actual listener process for Oracle and must be running for users to connect to the db.
lsnrctl is a command for controlling that listener (start, stop, etc). The status command will give you more detail than simply grepping the process.
If either process, pmon or smon fails, your database instance will terminate.