If you loose partition or filesystem integrity and need to re-partition or re-format the SystemRescueCd is for you. Comparable to the popular Ultimate Boot CD, and the Super GRUB Disk this cd is excellent for your toolkit. The most recent update sports PXE boot so you can test the ethernet card of thin clients for a bad PXE rom. Overall the combination of the tools incorporated on these three cd makes almost any computer problem solvable. http://www.sysresccd.org/Main_Page
With RAID1 configured by Debian Distro installers, you will have to install GRUB on all secondary drives. For this I use the Super GRUB Disk. http://supergrub.forjamari.linex.org/ Pop the CD in your drive, boot, click space to unpause a couple of time, select english, click Linux tools, then GRUB install. Install GRUB to all drives if you do not know which ones it is not installed on. It won’t hurt to install GRUB on a drive that already has it. After you do this, all the drives in your RAID1 array will be completely bootable.
If you are experiencing a lag that you believe is abnormal operation, before thinking it is a hardware issue it may prove to be software. I was experiencing a lag prior to the manufacturer boot splash; that screen with the press f10 button to configure the BIOS It would just hang there and not proceed to launch grub. A bad grub install can cause boot problems. I have corrected certain boot problems with a clean hard drive format, removing all primary and logical partition and performing a clean OS install.