How to truncate alert log file ??

Hi,

My alert log file has grown very big and I want to truncate it and start a new alert log file. How can I do this on a unix system while database is up.
Appreciate all the help.

Sanjay

Just
mv alert.log alert.log.save (or what ever). The Oracle server will then create another alert.log and start writing to it.

I have a cron job that goes out and renames all my alert.log files to alert.log. at midnight. I then re-touch the alert.log file. This allows me to run a find -mtime and delete a specified number of days of alert.log files.