On the other hand, we do try to be helpful, even if it is just prodding with questions. The ML6000 is a modular thing that can be configured in many ways with lots of options. So, for starters, we would need to know what you have. Is your tape library set up with fiber channel, SAS, iSCSI, or what? Is it something already on the network and you are just setting up a RedHat box to access it? Or is it the other way around. What have you done already?
In principle, you will want mt to be able to access the drive (or drives) as /dev/nst1 or similar. You will want mtx to be able to access and manipulate the library as a scsi device. You should have some documentation, some other sysadmins who have worked with it, or the vendor that could get you started. Then ask more specific questions here. If they don't specifically mention RedHat, look for general Linux/Unix setup instructions, drivers, etc.