Backing up the database without compromising performance

I have a data base with a size up to 120 Gb and I need do a backup every night.

The problem is that the system needs stand operative all the 24 hours.

In this moments the backup takes up to 2 hours to complete.

How I can do the backup without compromising server performance?

Thanks,
Andrés

120GB should not take 2 hours

• Do you have a separate disk array for backups, with a separate network interface to move the backups off the server?

• If you have Enterprise Edition, can you use mirror backups

• Can you do weekly full backups and daily differentials?

• Is backup compression turned on (Standard in SQL Server 2008 R2+, Enterprise only in SQL Server 2008)

And without more details, it will be hard to be more specific

StackExchange Database Administrators Q#46240, answer score: 9