From owner-freebsd-questions@FreeBSD.ORG Sun Aug 24 07:18:58 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 33CE21065676 for ; Sun, 24 Aug 2008 07:18:58 +0000 (UTC) (envelope-from m.seaman@infracaninophile.co.uk) Received: from smtp.infracaninophile.co.uk (gate6.infracaninophile.co.uk [IPv6:2001:8b0:151:1::1]) by mx1.freebsd.org (Postfix) with ESMTP id 9A8418FC16 for ; Sun, 24 Aug 2008 07:18:57 +0000 (UTC) (envelope-from m.seaman@infracaninophile.co.uk) Received: from happy-idiot-talk.infracaninophile.co.uk (localhost [IPv6:::1]) (authenticated bits=0) by smtp.infracaninophile.co.uk (8.14.2/8.14.2) with ESMTP id m7O7InAf062621; Sun, 24 Aug 2008 08:18:50 +0100 (BST) (envelope-from m.seaman@infracaninophile.co.uk) X-DKIM: Sendmail DKIM Filter v2.7.0 smtp.infracaninophile.co.uk m7O7InAf062621 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=infracaninophile.co.uk; s=200708; t=1219562331; bh=fiq4px4p+vCf7y Du4+fZyCOuTxMVUpkK86U6JfMdFbA=; h=Message-ID:Date:From:MIME-Version: To:CC:Subject:References:In-Reply-To:Content-Type:Cc:Content-Type: Date:From:In-Reply-To:Message-ID:Mime-Version:References:To; z=Mes sage-ID:=20<48B10B51.9030504@infracaninophile.co.uk>|Date:=20Sun,=2 024=20Aug=202008=2008:18:41=20+0100|From:=20Matthew=20Seaman=20|Organization:=20Infracaninophile|User -Agent:=20Thunderbird=202.0.0.16=20(X11/20080726)|MIME-Version:=201 .0|To:=20Gary=20Kline=20|CC:=20FreeBSD=20Mailing =20List=20|Subject:=20Re:=20Why=20/u sr/local/etc???|References:=20<20080824012442.GA46150@thought.org>| In-Reply-To:=20<20080824012442.GA46150@thought.org>|X-Enigmail-Vers ion:=200.95.6|Content-Type:=20multipart/signed=3B=20micalg=3Dpgp-sh a256=3B=0D=0A=20protocol=3D"application/pgp-signature"=3B=0D=0A=20b oundary=3D"------------enig0DA0876CF5E694A9425C2B33"; b=vCHY0fWFWjV 3N+DNWA5VjXFPALKP/QLbqNW/FdLGhoA8RM5DYr9D6NKHGqaBkbWn8tMF8E+6kCvIWE EICL8/16dOnGSP+aNN1KcgTW2YJ/oBCz7aHhGSiJQIE89eyLnlvy8mdydNg7mBBbYxM BNJh0NTwf6uTuLqBXmQBCADNIk= Message-ID: <48B10B51.9030504@infracaninophile.co.uk> Date: Sun, 24 Aug 2008 08:18:41 +0100 From: Matthew Seaman Organization: Infracaninophile User-Agent: Thunderbird 2.0.0.16 (X11/20080726) MIME-Version: 1.0 To: Gary Kline References: <20080824012442.GA46150@thought.org> In-Reply-To: <20080824012442.GA46150@thought.org> X-Enigmail-Version: 0.95.6 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enig0DA0876CF5E694A9425C2B33" X-Virus-Scanned: ClamAV 0.93.3/8080/Sun Aug 24 00:39:30 2008 on happy-idiot-talk.infracaninophile.co.uk X-Virus-Status: Clean X-Spam-Status: No, score=-2.6 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VERIFIED,NO_RELAYS autolearn=ham version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on happy-idiot-talk.infracaninophile.co.uk Cc: FreeBSD Mailing List Subject: Re: Why /usr/local/etc??? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 24 Aug 2008 07:18:58 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig0DA0876CF5E694A9425C2B33 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Gary Kline wrote: > This may have been covered too-often before, buy why can't > *everything* related to /etc hang off "/etc"? I can create a > symlink in /etc to /usr/local/etc named "loc" or "local". =20 > Thing is, why this isn't done by default? Mostly historical reasons. The typical Unix filesystem layout was developed in the days when disk capacities were measured in Megabytes and they were a lot less reliable than they are today. Hence it was important to have a separate root filesystem small enough to fit on one drive and containing everything needed to boot the system -- and ideally,= if your root disk failed, you'ld have a spare drive with identical contents to fall back upon. Other file systems were created generally on= e to a disk and mounted as required -- so you'ld have separate /tmp, /var, = /usr, /usr/local, /home etc. If the filesystem grew beyond what one disk = could support, you'ld have to create and mount a new filesystem on anothe= r=20 disk and move content onto it. RAIDing disks together to make larger=20 filesystems was developed as a response to the limitations of the hardwar= e of that generation, but in those early days it was unlikely you'ld be abl= e to boot from a RAIDed partition. Failures of disks providing other filesystems could be handled by recovery from backup, so long as you had that basic and as minimal as possible bootable root partition. Nowadays, the situation is turned on its head. Disks are very much larger than the space required to install the OS, and they are both reliable[*] and pretty cheap. Server class motherboards generally assume= you're going to mirror a pair of disks together to provide resilience. There are also any number of portable disk equivalents that a system can be booted off in an emergency: memory sticks, compact flash, live CDs etc= =2E all generally big enough to hold a complete bootable system. However there is no overriding reason to rearrange the filesystems. Oh, there are arguments about "does the root partition still need to be kept separate" (personally, I'd say no it doesn't: one big partition to hold it all is much simpler to administer, but opinions differ) but nothing that makes change imperative. I do think that there is potential for some sort of rearrangement due to the increasing popularity of virtualization and similar techniques, where= reusing filesystem content as far as possible pays big efficiency=20 dividends. I'd see filesystems divided into three classes depending on=20 content: generic -- user home directories, web content, databases, syste= m=20 sources, the ports tree etc. that you'ld want to share or be able to=20 migrate across all instances; arch specific -- kernel, binaries, shlibs, = /usr/obj, binary package collections which are tied to the CPU architectu= re=20 and the OS version and finally instance specific -- configuration data (= ie=20 /etc, /usr/local/etc), log files, temporary and swap spaces. It's not=20 excessively difficult to make this sort of split with existing layouts, but it is more complicated than it needs to be. Cheers, Matthew =20 [*] Well, compared to 20 years ago they are. --=20 Dr Matthew J Seaman MA, D.Phil. 7 Priory Courtyard Flat 3 PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate Kent, CT11 9PW --------------enig0DA0876CF5E694A9425C2B33 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEAREIAAYFAkixC1kACgkQ8Mjk52CukIyTdwCfWYror5j0PO9UdVtpKRdGhZNx 69EAn0Znb/UFpBKdcxAD1/NUxMCpZh0Y =6PXw -----END PGP SIGNATURE----- --------------enig0DA0876CF5E694A9425C2B33--