installed new hard drive - now can't find it

[Dana Holland]

It finally dawned on us to try Dell support since that's who we just 
bought the drive from.  It's a hardware RAID - they had us initialize 
the drives using the Array Configuration Manager, and now they have a 
couple of more commands they want us to run - supposedly after that the 
additional space will be visible.  However, they're suggesting that we 
do a full system backup before we run these last commands.  I know how 
to do a system backup on AIX, but I've never done one on Linux - I've 
always just tarred what was important to me to a tape or another box. 
Plus, this is further complicated by the fact that we have an Oracle 
database on this box.  Can anyone point me to directions for doing a 
system backup?  As usual, I'm searching the internet for the 
information, but we're getting into a crunch timewise.