On Mon, 2003-03-10 at 15:32, Andrew J Caines wrote: > Marc, > > > I?m currently developing a jail-management solution - I use a > > readonly mount_null for central software-management of the jails. > > The manpage was written May 1, 1995 - is using this tool still dangerous > > I have used it for read-only mounts since way back and have not have any > problems, including brief periods of high I/O. > > I'd have reservations allowing unique data on a read-write mount, however > I just did a few quick and simple tests of reads and writes on a rw null > mount on my 4.8-RC box with no apparent problem.
I seemed to be able to crash the kernel regularly under FreeBSD 4.5 when I used null mounts to share a read-only filesystem between jails. My application frequently rebuilt the jails by unmounting everything, wiping out the old jail subdirectories, writing new jail subdirectories, and remounting the shared read-only fs into each jail subdirectory. I gave up on null mounts and went back to having a separate copy of the entire filesystem for each jail. If null mounts work better now, I'll revisit it... Guy -- Guy Helmer <[EMAIL PROTECTED]> To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
