From owner-freebsd-questions Sat Aug 26 23:14:40 2000 Delivered-To: freebsd-questions@freebsd.org Received: from guru.mired.org (zoom0-144.telepath.com [216.14.0.144]) by hub.freebsd.org (Postfix) with SMTP id 3BE9237B423 for ; Sat, 26 Aug 2000 23:14:35 -0700 (PDT) Received: (qmail 23938 invoked by uid 100); 27 Aug 2000 06:13:57 -0000 From: Mike Meyer MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <14760.45477.402050.39137@guru.mired.org> Date: Sun, 27 Aug 2000 01:13:57 -0500 (CDT) To: Greg Lehey Cc: questions@freebsd.org Subject: Re: read only / filesystem In-Reply-To: <20000827135500.A88160@wantadilla.lemis.com> References: <78875170@toto.iv> <14760.37457.359972.176638@guru.mired.org> <20000827135500.A88160@wantadilla.lemis.com> X-Mailer: VM 6.72 under 21.1 (patch 10) "Capitol Reef" XEmacs Lucid X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`;h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Greg Lehey writes: > On Saturday, 26 August 2000 at 23:00:17 -0500, Mike Meyer wrote: > > Greg Lehey writes: > >> On Thursday, 24 August 2000 at 23:49:17 -0700, R Joseph Wright wrote: > >>> Or is it easy enough to simply remount / rw when changes to /etc are > >>> needed? > >> You can do this, but you can't go back to an ro mount. > > Uh - why not? > It's not reliable. There are some problems with dirty buffers when > you make the file system read-only again. I forget whether it's data > corruption or a panic, but the only safe way to do this is to umount > the file system and remount it r/o, obviously not an option here. Sounds like an OS bug. The mount system call should make sure the file system is in sync before doing the udpate mount. You could, of course, do the sync's by hand until that happens.