I need to find some backup software to save some of data offsite. We have a new server with a lot of space set up in a new data center and we need to find some software that will let us save some data to it remotely. Here are the requirements for the software.
-scp from linux
-scp from windows
-email notifications
-scheduling
-compress before sending

if anyone know some good backup software ,please let me know.
thanks!

Most admins I know simply write their own scripts to do this. Linux Backup Software is kind of an oximoron; unless you are backing up Windows' registry and locked files, then you'll need special software for that.

do you have such kind scripts I can reference?

If you want to write your own scripts, use rsync.

If you need some prebuilt application to handle scheduling, notifications and such, might want to check out bacula and or amanda.

rsync is probably best particularly if you are doing offsite incremental backup.

Basically you can create tarballs and copy it over to a remote computer or external USB drive. Unlike Windows, tar copies most files even if they are locked. google 'Linux backup scripts'. You may want to get yourself familiar with writing bash scripts.

Why would you use tarballs? Wouldn't running rsync be enough? I admit that I am not doing offsite with rsync right now but I run rsync in a script to back everything up daily to a removable harddrive. The first time it took hours to back up the server this way (about 70gb worth) but the daily routine takes only 5 minutes now. If tarballs were used, I would think the total process time would increase (ie first make the tarballs, then rsync to external site or drive and since the tarball changed, the whole thing would need to be transfered). Would that be correct?

Basically you need to put into a script what you would type in the command line in order to backup your data. Google 'Linux backup scripts'

For an rsync script, here is what I use. Now, this is for backup to a removable harddrive, not a external site. If you search on the internet or check out http://samba.anu.edu.au/rsync/ you can figure out how to make this an off site backup.

The exclude section ensures that some files aren't backedup. Note, the directory "/backup/" is in the excludes because that is where I mount the external harddrive during the backup.

This isn't by any means perfect but it has worked quite well so far. Much of this I got from this site. I can't find the thread where it was but it is here somewhere.

I'd agree not using tarballs every single day. That's just making daily full backups which takes up space.

In my own setup for my personal servers, I have a full weekly script that creates larger tarballs and all other days I have an rsync script that makes the incremental changes.

rsync stands for remote sync and it does not compress. rsync is better for small non-compressed backups of a few megabytes, but it is not good by itself for full backups of 70GB; then you'll need to compress. rsync is designed to syncronize files in separate systems. Hence the 'sync' in the name. tar stands for Tape Archiver. It was created decades ago exclusively for backing up to tape on Unix systems.

For daily differential or incremental backups use 'find' and 'tar'.
With find you can discover all the files that are less than one day old or less than a week old then you pipe it onto tar to compress and store the tarball onto a remote drive or tape. That's the way most guru's do it.