Backups all of a sudden varring in time to finish

[zman24]

what used to take 3 hrs to finish now vary from 3hrs to 20 hrs. I have noticed in the logs the backups that take the most time have this in the logs Backup Set #4 on Storage Media #5. There could be several of these with different  sequencial #s. The thing I am thinking maybe I am missing is this. In Options under Media managment I have the overwrite set to partial. What I want out of my backups are to do a complete full backup each night, completely erasing the disk every night. Do I need to change this  option to none under media management? And will this maybe fix the hrs taking to backup. I am using Backup Exec 11d rev 7170
Thanks
Zman

[chicojrman]

Typically when this happens I ask have you done anything recent like Windows updates or updates to BE?

[CraigV]

Your tape/disk will be overwritten when it's retention period has lapsed.
You can set your overwrite option to Non under Media Management. This will make sure there is no prompt to overwrite media, and as long as the media has expired, it should do this.
The prompt will make your backups take longer until input is received.
Backup times can also increase if you have load on a server or network, run an antivirus scan at the same time as a backup etc.

[Ken_Putnam]

While Craig's suggestion of setting the Global Overwrite to NON will work, I've seen some REALLY strange behavior with this setting

Rather than that, set the OPP of the media set(s) written to this disk so that when you no longer need the data, it can be automagically overwritten.

For example, if you need the data for a week, set the OPP to 6 daysk, two weeks to 13 days, etc

[MitchR]

I've also seen things like this happen with the server has lots of files in user by users.  In some cases, BE will try to lock a file, and delay the job mid-process.

If possible, run the backups on days/times when user activity will be low.