BRARCHIVE Failed due to Lock.bra

The error:
BR021I Please delete file /oracle/<SID>/saparch/.lock.bra if BRARCHIVE was killed

The .lock.bra file is a locking mechanism which is created every time BRARCHIVE starts to make sure only one session of BRARCHIVE is running at a time. When BRARCHIVE is ending successfully, it deletes this lock file, but when BRARCHIVE are killed or stops abnormally for some reason, it often fails to delete the lock file.  So, in order to overcome this issue, we need to remove the lock.bra file in the operating system level.

1. Login to the affected operating system. Go to /oracle/<SID>/saparch/ directory and find the .lock.bra file. Remove it now!
# cd /oracle/<SID>/saparch/
# ls
# rm -rf .lock.bra