I would like to get some input from you linux system administrators out there.  
I was discussing the use of linux with one of the decision makers of our IT 
department, and he issued some concerns about Linux, that I was not properly 
prepared to address.  I can sort of answer some of this, but I would like 
your input so that I might be better prepared to discuss.

He said, " We don't own any Linux-supported tools for single sign-on across 
servers (though you've indicated that they can participate in the Windows 
domain), tape back-up or system monitoring."

How can these three issues be addressed with included tools, open source, or 
even proprietary products.  He's not afaid to spend a little money, as he 
deals with huge software contracts worth hundreds of thousands.  He might 
even be somewhat more comfortable with a vendor solution.  So, feedback?

1. Single signon across servers
2. tape back-up - automated I assume
3. system monitoring - performance, capacity, security

Thanks,
Jim