On 20 Aug 2002, Michael Wright wrote: > Here is another question, > > How are 2 disk in a RAID 1 setup kept in sync on a Promise Fastrak 100? > > I really want to know if the "hardware" does any sort of synchronization > in real-time. I am concerned that fsck could screw your file-system > completely if it tries to repair an out of sync file-system. Hardware does NOTHING. Ide raid controllers are just usual ide controllers with a special bios supporting RAID. While the system is booting, the BIOS handles all raid-things, until the kernel is active. Then the kernel takes over control. I took a look at the source code of pdcraid (kernel 2.4.17). There is no piece of code which ensures synchronisation of the disks. If the system should crash or something you mentioned and the disks go out of sync, all bad things can happen... If the system crashes, best to do would be go to the bios and resync the disks there manually. I have a hpt ide raid controller and had two disks out of sync, because linux used only one of the disks.. no resync action happened ever, neither from bios nor from the windows driver.. Viele Grüsse, Thorsten -- Thorsten Jungblut Universität Koblenz, Fachbereich Informatik http://www.netcorner.org/
