From owner-freebsd-stable Tue Apr 25 8:30:38 2000 Delivered-To: freebsd-stable@freebsd.org Received: from point.osg.gov.bc.ca (point.osg.gov.bc.ca [142.32.102.44]) by hub.freebsd.org (Postfix) with ESMTP id DF46C37BE97 for ; Tue, 25 Apr 2000 08:30:32 -0700 (PDT) (envelope-from Cy.Schubert@uumail.gov.bc.ca) Received: (from daemon@localhost) by point.osg.gov.bc.ca (8.8.7/8.8.8) id IAA29494; Tue, 25 Apr 2000 08:30:28 -0700 Received: from passer.osg.gov.bc.ca(142.32.110.29) via SMTP by point.osg.gov.bc.ca, id smtpda29490; Tue Apr 25 08:30:22 2000 Received: (from uucp@localhost) by passer.osg.gov.bc.ca (8.9.3/8.9.1) id IAA07614; Tue, 25 Apr 2000 08:30:21 -0700 (PDT) Message-Id: <200004251530.IAA07614@passer.osg.gov.bc.ca> Received: from localhost.osg.gov.bc.ca(127.0.0.1), claiming to be "passer.osg.gov.bc.ca" via SMTP by localhost.osg.gov.bc.ca, id smtpdNE7604; Tue Apr 25 08:30:18 2000 Reply-To: Cy Schubert - ITSD Open Systems Group X-OS: FreeBSD 3.4-RELEASE X-Mailer: nmh 1.0.4, Exmh 2.1.1 X-Sender: cschuber To: Doug White Cc: Cy Schubert - ITSD Open Systems Group , Matthew Dillon , freebsd-stable@FreeBSD.ORG Subject: Re: Linux Emulation Root (was: Re: Linux emulation scripting fix to be committed to 5.x and 4.x wednesday) In-reply-to: Your message of "Mon, 24 Apr 2000 14:07:56 PDT." Date: Tue, 25 Apr 2000 08:30:18 -0700 From: Cy Schubert Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In message , Doug White writes: > On Sun, 23 Apr 2000, Cy Schubert - ITSD Open Systems Group wrote: > > > In message <200004231835.LAA62963@apollo.backplane.com>, Matthew Dillon > > writes: > > > I intend to commit this to -current and immediately MFC it to -stable > . > > > I don't expect there to be any controversy though I'm sure there is a > > > cleaner way to do it. > > > > On a semi-related topic, it would be handy to have a feature, > > environment variable, table in the kernel, a sysctl variable, etc., to > > set the Linux emulation root to the real root. For example, the backup > > component of Legato for Linux (nsrexecd and friends) runs nicely on > > under Linux emulation, however, recovering files in the root directory > > sees them placed in the Linux emulation root directory. > > I ran into a similar problem with ADSM -- it would happily back up > /compat/linux thinking it was backing up /. I patched the linux mode KLD > to disable the /compat/linux path munging. I tried to submit it back but > was shot down; the emulation people wanted a more general method, which I > assume included a way to define your own 'linux root'. The discussion got > lost some time after that in -emulation. Legato for Linux backs up /, it just cannot restore to it. Instead if you restore for example restore /etc/rc.local, it's restored to /compat/linux/etc/rc.local. Any redirection using the Legato recover subcommand relocate to /etc does not work. Mounting a unionfs (or nullfs) of / on some other directory and redirecting the restore to it does work. > > > To work around this I've used a union filesystem that mounted / on > > another mount point and redirected my restores to it. > > Unforunately union mounts are known unstable. Nullfs mounts have always caused me problems, however unionfs mounts under 3.4 and 4.0 haven't caused my FreeBSD systems to crash yet. As a matter of fact I set up yet another one on my network at home, NFS mounting /compat on my 486DX33 from my P120 and union mounting /compat/linux on top of it so it could write the ldconfig cache. No problems so far. > > Doug White | FreeBSD: The Power to Serve > dwhite@resnet.uoregon.edu | www.FreeBSD.org > Regards, Phone: (250)387-8437 Cy Schubert Fax: (250)387-5766 Team Leader, Sun/DEC Team Internet: Cy.Schubert@osg.gov.bc.ca Open Systems Group, ITSD, ISTA Province of BC To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message