Abrupt increase in alert SID .log file size

Question

alert<SID>.log file is abrubtly increasing in size which is in process filles up a disk space, hence further no DB login.
I shutdown the database, took a bakup of the alert log file, nullified the alert log ( using cat /dev/null > alert.log) and started up the database.
As of now, its okay, but can I nullify this alert log file while the database is up and running..???

Answer 1

It is better to write a simple shell script to housekeep the alert.log.
Below is an example
if [ `ls -al $ALERTLOG | awk '{print $5}'` -gt 2500000 ]
then
cp -p $ALERTLOG $ALERTLOG.`date +%d%m%y`
cat /dev/null > "$ALERTLOG
gzip $ALERTLOG.`date +%d%m%y`
find "$ALERTLOGFOLDER "-name *.gz -mtime +10 -print -exec rm {} \;"
fi
Also, you need to housekeep adump, bdump, cdump ... etc folders