[Info-vax] Unpleasant Disk Shadowing Surprise

[JF Mezei]

Bob Koehler wrote:

>    If your definition of real-time can't handle 3 minutes of
>    interruption, then you probably need to engineer a different solution
>    than the kind of shadowing approach you're using now.

I seem to recall being told that VMS would seamlessly continue to run
after the loss of a disk.

Perhaps it is expected that the mount verification (which Rob Brooks
confirmed would kick in) would complete in a second or two.

My guess is that one disk's failure ruined the SCSI bus and prevented
VMS from talking to the other disk until the first one died and allowed
SCSI to function.

For proper fault tolerance, you would want to have 2 SCSI controlere.