I Have two 40G HD and want to user Raid(ITE8212) do Raid 1, i have setting the raid BIOS with raid 1,boot with slackware Disk1 and choose the test26.s,it display hde for raid1(40G),and I fdisk /dev/hde.after it can install slackware very well,and do raid 1.
But Now I have on server it have a exiting system(slack10.1),and i want to use Raid1 ,but no want to reinstall the system ,what can I do?
pls help me??

In my case, I have an hda drive that I normally work in, but I copy the hda2 partition to hde2 for backup & use if/when I crash my main partition. One warning, this method will not allow you to boot from the partition that you are going to copy. I actually created an hda3 partition (about 500 mb) & loaded a minimal Slackware installation (command line & networking only) into it to do this job. If you are not planning to keep hda in the box, using a LiveCD will work also, as long as it uses a recent 2.6 series kernel, so that you have the IT821X driver. The most recent SLAX works well. I will assume that you are booting from a LiveCD. So...
Install your raid drives & set up the ITE bios. Install the drive that has the partition(s) you want to copy as hda (or hdb, or whatever). Boot from the LiveCD.

Note: I have trouble reading/writing large amounts of data to/from /dev/hde if DMA is not set on the drive. Use:
I also insert this line into a working system in /etc/rc.d/rc.S, right up front, after the path definition, so that it will be applied before much is written to the drive. Even fsck can cause the drive to quit.

Now, use (c)fdisk to make the partitions you will need on /dev/hde. Do not forget swap. Format the partitions as you wish. Mount the main partition on /dev/hde/ somewhere. Type the command:
substituting the actual mount points. The copy will take several minutes & should complete with no errors. Repeat the above command for any other partitions that you use. In my case, I only use "/", so only do it once. Now, modify the /etc/fstab file on /dev/hde, so that it points to the right partitions. You will also need to install a bootloader. I install GRUB, from the slackware-current/extra directory & start with the grubconfig program, then modify menu.lst from there. If you use LILO, I won't be much help, I haven't used it for a long time. Although I assume that you could boot from the hda partition you have and install LILO to hde from there.
This should get you started. If you have any questions, please post.
Regards,
Bill