Hope somebody here can help me..

ive installed fedora core 3 with 3 hard drives in a raid using the install process but now its all up and running i need to add another hard drive and cant work out how to do it....

Im sure its quite simple just havent got it yet

Please Help!!!!!

With three drives I can only assume your running RAID 0.
Adding another drive is no problem accept you should "pair" drives of same size together to get the best performance. If the new drive you want to introduce is bigger than the other drives then simply partition it to have at least one partition = to the other drive largest partions size and leave the leftover space in separate partition.

If your using SoftRaid - Well its 50/50 if the leftover space will be used. HardRaid will usually use it but of course not in a Raid fashion i.e.: Not Raid 0 or 1.

You WILL lose data from your drives no matter if they are Raid 0 or 1; because that is how you have mapped them.

If SoftRaid - read the SoftRaid documentation and driver source to find out the true details. If HardRaid read the manual and converse with the manufactures tech support to get the facts.

Cheers. Grahame.

Forgot to add that maybe, just maybe LVM will handle the remapping of the Raid drives. I cannot say which way for sure - You'll just have to try it out and wish for the best outcome. Under SuSE LVM I believe it does the remapping itself and secures the data. Not sure about other distributions or LVM programms (they may all be the came generic program - here's hoping).

I'd start with LVM first and formost before taking any actions I posted previously.
Definitly read the LVM documentation completely and work out the process first until your comfortable.

Cheers. Grahame