thib wrote:
Clive McBarton wrote:Good point, that is probably important. ext3.Well then I would suggest going through the tune2fs(8) manpage and find out what could be.. tuned. You know what? I think your first suggestion is a good one - look at the mount count configuration for a starter.If nothing works for you, you'll have to study the filesystem in depth.The question is, then, as usual; why is it important? (Sorry to ask again, maybe you don't think it is relevant.)-thib
It is almost certainly the mount count.It is worth noting that the read-only mount prevents writes via "normal" filesystem functions, only.
You could still have a write done directly to the device, using the reverse of what the OP did to get the checksum, and completely destroy the disk content.
Or, more to the point, use a "disk editor" and twiddle a bit here and there.To get an absolute, no write, ever, to the device, the OP will need to figure out how to force read only permissions on the device /dev/sda1, across boots.
Bob McGowan