From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vn0-f45.google.com ([209.85.216.45]:33380 "EHLO mail-vn0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751477AbbEDXkI (ORCPT ); Mon, 4 May 2015 19:40:08 -0400 Received: by vnbf1 with SMTP id f1so15835730vnb.0 for ; Mon, 04 May 2015 16:40:08 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <20150412201107.GA4711@hungrycats.org> Date: Mon, 4 May 2015 16:40:08 -0700 Message-ID: Subject: Re: mlocate/updatedb and btrfs subvolume mounts From: "G. Richard Bellamy" To: Duncan <1i5t5.duncan@cox.net> Cc: linux-btrfs Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Sun, Apr 12, 2015 at 9:12 PM, Duncan <1i5t5.duncan@cox.net> wrote: > > Zygo Blaxell posted on Sun, 12 Apr 2015 16:11:07 -0400 as excerpted: > > > Since these are simple binds (not rbinds), they don't see any other > > filesystems, period. They do see btrfs subvolumes, though. > > Tho... for systemd users... > > Do note that systemd plays with the kernel's shared-subtree "private" > default, switching it to shared for /. I like to think I know a bit about a thing or two. I've read both Zygo and Duncan's probably cogent responses. My brain hurts, and I am just not getting it. If I am to understand correctly, and specific to my OP, the problem with updatedb et al. on my system is that /, /home, /var, /opt and /var/lib/libvirt are all subvolume mounts - which appear as bind mounts. Thus the PRUNE_BIND_MOUNTS prunes ALL mounts, and updatedb sees nothing. Everything else is a blur when we start talking about "mount --bind / /.binds/root" Oh wait, maybe I get it now... By running "mount --bind / /.binds/root" and running updatedb in "/.binds/root" while still allowing it to see binds, I am certain to get a an mlocate db, and it won't ever see anything outside that explicit hierarchy. Something like that? -rb