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more questions on setting up autofs on C7

Hi!

Thanks to some of you I got autofs set up on my C7 netbook for
mounting local cifs filesytems.

Now I want to do something on my C7 desktop machine, that seems to
me to be a little different, and I"m not sure how to do it.

I have an external RAID1 box that attaches via USB. It is/will be
nearly always /dev/sdc, but being USB I can't guarantee that it
will always be found there.

accordingly, in my /etc/fstab I have an entry that mounts it via its
UUID:

UUID=09bfc97a-8db2-46de-b4dd-427da19b114 /mnt/backup xfs defaults,noauto,users 0 2

and I'm wondering how to specify that in an autofs recipe instead...

If doing cifs mounts, /etc/auto.master may contain this line:

/mymount /etc/auto.mymount

then there would be a file /etc/auto.mymount that contains a line
similar to this:

winbox -fstype=cifs,rw,noperm,user=sushi,pass=yummy ://winbox/getme

so, in my case, the USB drive contains an xfs filesystem. would I
do something like this:

in /etc/auto.master:

backup /etc/auto.backup

and in /etc/auto.backup

backup -fstype=xfs,defaults,noauto,users :UUID=09bfc97a-8db2-46de-b4dd-427da19b114

Would that be expected to work, or am I all overlooking something obvious?

Thanks in advance for your advice!

Fred

Comments

Re: more questions on setting up autofs on C7

By Gordon Messmer at 08/23/2017 - 15:03

On 08/21/2017 07:23 PM, Fred Smith wrote:
In auto.master, the first field is a directory, so it should be "/backup".

Debian's documentation says you shouldn't need to prefix UUID with a
':', so remove that from auto.backup if the configuration you described
doesn't work. Alternatively, you could specify its location as
":/dev/disk/by-uuid/<the disk id>".

Re: more questions on setting up autofs on C7

By fred smith at 08/23/2017 - 16:06

On Wed, Aug 23, 2017 at 12:03:12PM -0700, Gordon Messmer wrote:
Ok, when I actually tried it, I did it this way:

/etc/auto.master (excerpt):

/mnt /etc/auto.mnt

and /etc/auto.mnt:

backup -fstype=xfs,defaults,noauto,users,rw :UUID=09bfc97a-8db2-46de-b4dd-427da19b1143

and lo and behold, it works!

but...

I have a couple of other networked filesystems (cifs) that I have always
mounted in /mnt. so, after accessing either of them, systemctl status autofs
shows me this:

Aug 23 15:46:02 fcshome.stoneham.ma.us systemd[1]: Starting Automounts filesystems on demand...
Aug 23 15:46:02 fcshome.stoneham.ma.us automount[11265]: setautomntent: lookup(sss): setautomntent: No such fil...ory
Aug 23 15:46:02 fcshome.stoneham.ma.us systemd[1]: Started Automounts filesystems on demand.
Aug 23 15:50:04 fcshome.stoneham.ma.us automount[11265]: key "syno-fredex" not found in map source(s).
Aug 23 15:50:04 fcshome.stoneham.ma.us automount[11265]: key "syno-public" not found in map source(s).

the first error regarding setautomntent seems to be pretty universal,
as I see lots of questions about it (and bugs filed against Fedora and
RHEL) but no actual solution. the consensus is that it doesn't seem to
prevent autofs from working. (there is a workaround that I haven't
tried, and mention of a patch to sssd that I also haven't tried, and
which apparently hasn't made it into RHEL 7.3 or Centos7.x).

so, the two lines saying: Key "syno-fredex" or key "syno-public"
appear whenever I try to access one of those two filesystems. I AM NOT
USING AUTOFS TO MANAGE THEM. they were mounting in /mnt, just like the
automount I was asking about. thinking since autofs was looking in /mnt
for the backup mount that it was getting all confuzzled, I changed the
mount point of those other two filesystems, changed their entries in
/etc/fstab, reran systemctl restart autofs then touched one of those cifs
filesystems. Voila! the errors still appear in the output of systemctl
status autofs.

Everything still appears to work, but I'm puzzled by those two errors.

Anyone got any good ideas on this?

thanks in advance!

Fred

Re: more questions on setting up autofs on C7

By Gordon Messmer at 08/23/2017 - 16:59

On 08/23/2017 01:06 PM, Fred Smith wrote:

You're using autofs to manage /mnt, so any time that *any* process
attempts to access /mnt/syno-fredex or /mnt/syno-public, you'll get
those errors. That's how autofs works: access attempts in an autofs
managed directory get passed to autofs, which looks at its maps to
determine how to mount the path being accessed. The error you see is
autofs telling you that something is trying to access "syno-fredex"
under /mnt, but it doesn't have a map indicating how to mount a
filesystem in a directory of that name.

Re: more questions on setting up autofs on C7

By fred smith at 08/23/2017 - 17:31

On Wed, Aug 23, 2017 at 01:59:23PM -0700, Gordon Messmer wrote:
yeah, that's what I figured.

so I created /mounts and moved those two mounts to that directory.
the restarted autofs, but the errors still come when accessing
those two mounts.

do I need to reboot or something to get autofs to forget about them
being in /mnt?

Thanks again!

Re: more questions on setting up autofs on C7

By Gordon Messmer at 08/23/2017 - 23:53

On 08/23/2017 02:31 PM, Fred Smith wrote:

No, you need to figure out what program, not autofs, is trying to access
/mnt/syno-fredex and /mnt/syno-public.

You moved the mounts, but some program still expects those paths to
exist. autofs is just telling you that some other program is still
looking in that location.

Re: more questions on setting up autofs on C7

By fred smith at 08/24/2017 - 21:55

On Wed, Aug 23, 2017 at 08:53:17PM -0700, Gordon Messmer wrote:
Gordon, thanks for the followup.

I have a desktop icon for opening a window in each of those two mounts
(the mounts occur at system boot), the icons are backed up by .desktop files:

cat NAS-fredex.desktop
#!/usr/bin/env xdg-open

[Desktop Entry]
Version=1.0
Type=Link
Icon[en_US]=system-logo-icon
Name[en_US]=NAS-fredex
URL=/mounts/syno-fredex
Name=NAS-fredex
Icon=/usr/share/icons/mate/48x48/places/network_local.png

cat NAS-public.desktop
#!/usr/bin/env xdg-open

[Desktop Entry]
Version=1.0
Type=Link
Icon[en_US]=system-logo-icon
Name[en_US]=NAS-public
URL=/mounts/syno-public
Name=NAS-public
Icon=/usr/share/icons/mate/48x48/places/network_local.png

if I click one of those then run systemctl status autofs I see one
of those errors show up. If I click on it again, there are two
errors. if I click on the other one, a third error shows up.

nothing else I've tried seems to cause them to show up.

as you can see, neither of them refers to the old mount point on /mnt.

I know you can't look thru my computer and see what's wrong, but I'm
puzzl-ified, since /mnt/syno-public isn't mentioned anywhere in the
.desktop files. If you can think of anything else that might be happening,
I'd appreciate your wisdom.

thanks once again!

Fred

Re: more questions on setting up autofs on C7

By Gordon Messmer at 08/25/2017 - 02:04

On 08/24/2017 06:55 PM, Fred Smith wrote:

Does your file manager have some other link to the old locations? A
"favorites" entry? Something in the sidebar? More than likely, your
file manager is trying to check the old location, not for its primary
view which is /mounts/something, but for some other reason.

Re: more questions on setting up autofs on C7

By fred smith at 08/25/2017 - 11:32

On Thu, Aug 24, 2017 at 11:04:05PM -0700, Gordon Messmer wrote:
don't think so. I'm running the Mate desktop. Original install was
Gnome (which is I assume what you are thinking of) but I never use
it, can't stand Gnome-3.x.

Don't know of anything in mate that would do th at, but I'll do some
digging around.

thanks once again!

Re: more questions on setting up autofs on C7

By Gordon Messmer at 08/25/2017 - 12:37

On 08/25/2017 08:32 AM, Fred Smith wrote:

You can always look the hard/slow way:

find ~ -type f -exec fgrep /mnt/syno {} +

That command should locate any files that refer to the old mount locations.

Re: more questions on setting up autofs on C7

By fred smith at 08/25/2017 - 23:36

On Fri, Aug 25, 2017 at 09:37:59AM -0700, Gordon Messmer wrote:
a bunch of things that look merely like log files.

so, in the meantime I did the update for all the files sitting in
the CR repo. rebooted. now the problem is gone. Go figure.