Jail to jail network performance?

[Oliver Fromme]

[Sorry, this is a late reply, but might be helpful.]

Daniel Gerzo <danger at rulez.sk> wrote:
 > Hello Brandon,
 > Thursday, September 15, 2005, 5:17:57 AM, you wrote:
 > > [...]
 > > nullfs looks interesting. I was thinking about sharing files
 > > between jails using NFS, but it looks like nullfs would do the trick
 > > with better performance. Although the bugs section of the man page
 > > for mount_nullfs is rather scary. Does anyone have any experience
 > > with it? Does it actually work?
 > 
 > btw unionfs is interesting as well, but the BUGS section is pretty the
 > same :)

Another possibility is to use union mounts (i.e. using the
"-o union" mount flag with a regular mount).  This works
without problems and is very stable, but it is a little
less flexible than UNIONFS (or NULLFS) because it merges
only the directory entries at the mount point.

 > > If the point here is to make /tmp/mysql.sock show up in another
 > > jail's file space, can I use a symlink instead? Can a jailed process
 > > see the target of the symlink?
 > 
 > I read that using such a symlinks has security impacts.

Symlinks within a jail cannot point to targets outside of
that jail.

Best regards
   Oliver

-- 
Oliver Fromme,  secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing
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