Question: At the startup command,
we are facing ORA-00445 error PMON does not start even after 120 sec at the
time of instance starting up. How do I resolve the ORA-00445 error and
docs note that the ORA-00445 error happens when a background process cannot
ORA-00445: background process "string" did not start after string seconds
Cause: The specified process did not start after the specified time.
Action: Ensure that the background did not die and leave a trace file.
You start troubleshooting an
ORA-00445 error by examining your alert log and check for trace files in the
bdump (background_dump_dest) directory.
I have seen the ORA-00445
because the OS is still holding the SGA RAM after a previous crash.
First, run an “ipcs –pmb”
command and see if you have leftover RAM segments from the last instance.
If you find held RAM, run the ipcrm command to remove the segments.
Here is how to
check for held SGA RAM on the OS.
If PMON fails on startup,
it’s almost always because of one of these conditions:
Leftover memory segments
from a previous instance crash.
parameter settings in SQL*Plus ($ORACLE_HOME, $ORACLE_SID).
Permission issues with
the Oracle executables.
Not enough CPU/RAM
resources for the startup to complete.
In any case, the associated
trace file will give you the exact reason for the ORA-00445 error.