I have added a 7 disk Raid 5 array. This is a powervault 220s from Dell which provides the hardware raid.

How do I partition this array? I can see the individual disk device files.
But if I were to partition one of those the data would be all on one disk instead of striped which would negate the hardware Raid 5.

Is there a device file that references the whole raid? When I am in Red Hat it shows the Raid as being a system device with device file /dev/sg2.

An fdisk on /dev/sg2 just hangs.

Thanks for any help.

When using a Dell PERC and a RAID 5 the logical drive comprises of all the drives and the striping is in the BIOS and away from the operating system. So the O/S should see one big disk minus one complete hard disk space which is what supplies the redundancy. You can't negate the stripe from a hardware BIOS controlled RAID 5. If it's a true hardware RAID which PERC's do then the operating system has no idea how many physical hard disks there are that make up the RAID array when it's a level 5 RAID.

The utilities you speak of or are asking about are available on your PowerVault CD if it's a later revision that includes Linux utilities. Other than that there's also the Dell OpenManage Server Assistant which also has drivers, utilities and documentation for Linux usage which again must be a later rev of that CD. I'd suggest looking at http://support.dell.com for the RAID utils if RAIDTOOLS2 won't work for you.

As for fdisk hanging, make sure you have the Linux driver from Dell.com and not the one that come with your Operating System. Before you install the driver also check the Dell.com Support website for any notices and/or firmware updates that the controller might require to install the Linux driver and the utility if it's a Dell PERC.

And as a note... if you see more than one disk or the new disk you haven't added into the current array or you didn't initialize or scrub the RAID 5 array. When adding a drive you select or tag it from the CTRL-A or CTRL-M the process of which is too detailed for me to go into here. The complete howto is at http://support.Dell.com.

There's a complete explanation of RAID types here at LinuxQuestions.org in the Linux Wiki section.