Satoshi Asami writes: However, if I try to mount it from B read-only while A is mounting it read-write, it succeeds. This looks dangerous, as A writing data onto the disk could cause B's cache to go stale without B knowing it.
Just about as dangerous al letting A mount it read-only, and then B mounting it read-write. Only in this case, nobody has a chance to know that something is amiss, and since you probably are letting this happen automatically at OS startup, the chances of a RO mount being followed by a RW one are about the same as the other way 'round. You're going to have the problem regardless of whether mount pays attention to the clean flag. If you are worried about a RO mount getting corrupted, don't modify the partition out from under it on another machine. To Unsubscribe: send mail to majord...@freebsd.org with "unsubscribe freebsd-current" in the body of the message