[9fans] import/export -B

[9fans] import/export -B

[Steve Simon]

I am a little confused by import/export -B (backwards).

The only bit I don't get is why you have to supply a mountpoint to import.
Surely import will always be running from listen and as such it will not
be in any useful namespace so why mount anything?

from the manpage:

          Suppose that the machine moscvax has access to a private
          file server containing public web pages that need to be
          served by the less-trusted server webvax.  Webvax runs the
          following listener (see listen(8)) on TCP port 999:

               #!/bin/rc
               import -B -s rowebfs /usr/web /bin/restarthttpd

          When moscvax boots, it runs

               exportfs -R -r /usr/web -B tcp!webvax!999

          to serve a read-only copy of /usr/web to webvax.  When
          webvax gets the call, import mounts the served tree onto its
          own /usr/web and then runs /bin/restarthttpd to restart
          httpd(8).

It seems to me that my restarthpptd script will be
		'unmount /usr/web; chmod 600 /srv/rowebfs'

I find it strange that the mountpoint is not optional (as long as -s srv names exists).

perhaps I am missing somthing? or maybe its just a quirk?

-Steve

Re: [9fans] import/export -B

[erik quanstrom]

> The only bit I don't get is why you have to supply a mountpoint to import.
> Surely import will always be running from listen and as such it will not
> be in any useful namespace so why mount anything?

would it make more sense if it instead said "root of tree to be mounted"?

- erik