On Wed, 2021-03-10 at 22:35 +0800, Ed Greshko wrote:
On 10/03/2021 20:57, Patrick O'Callaghan wrote:
>
> [Sorry for the long delay, but other stuff intervened.]
>
> I've come back to this now and started experimenting incrementally. As
> a first step, I just want to automount/unmount, ignoring the power-
> on/off part for now, i.e. the device is already powered on. This is my
> /etc/fstab entry:
>
> UUID=6cb66da2-147a-4f3c-a513-36f6164ab581 /raid ext4
rw,noauto,user,x-systemd.automount 0 0
>
> and /etc/systemd/system/raid.automount (copied from your example):
>
> [Unit]
> Description=Automount /raid
>
>
> [Automount]
> Where=/raid
> TimeoutIdleSec=10
>
>
> [Install]
> WantedBy=multi-user.target
>
>
> I've rebooted, and the device starts up mounted:
>
> # findmnt /raid
> TARGET SOURCE FSTYPE OPTIONS
> /raid systemd-1 autofs
rw,relatime,fd=52,pgrp=1,timeout=10,minproto=5,maxproto=5,direct,pipe_ino=24910
>
>
> though I'm not sure why as nothing is accessing it. It also remains mounted,
despite the timeout.
>
> Any thoughts?
My first thought is that you're doing things a bit different than what I did.
You have an entry for your disk in the fstab. My understanding is that when an entry is
in fstab mount unit
files will be auto generated. I don't have fstab entries for my automounts. I
can't say that I know it is wise
to mix the methods.
Using my /aux as the example. When unmounted I see...
[root@meimei ~]# findmnt /aux
TARGET SOURCE FSTYPE OPTIONS
/aux systemd-1 autofs
rw,relatime,fd=53,pgrp=1,timeout=60,minproto=5,maxproto=5,direct,pipe_ino=26036
But when mounted
[root@meimei ~]# findmnt /aux
TARGET SOURCE FSTYPE OPTIONS
/aux systemd-1 autofs
rw,relatime,fd=53,pgrp=1,timeout=60,minproto=5,maxproto=5,direct,pipe_ino=26036
/aux nas:/volume1/aux nfs4
rw,relatime,vers=4.1,rsize=131072,wsize=131072,namlen=255,soft,proto=tcp6,timeo=600
I think I would first try removing (commenting out) the fstab entry and creating
raid.mount file in /etc/systemd/system/
with the contents.
[Unit]
Description=mount raid
[Mount]
What=/dev/disk/by-uuid/6cb66da2-147a-4f3c-a513-36f6164ab581
Where=/raid
Options=rw,user
Type=ext4
[Install]
WantedBy=multi-user.target
At this time I've only used automounts for nfs mounts. I'd try it with local
disk if it weren't for the late hour.
Also, due to the late hour, I seem to recall seeing something about working with
automounts and external devices
and conflicts arising due to the interference of udev. But I may be mixing things. So,
I'd first see if making the
above changes has any effect.
A couple of things:
1) I used fstab because the systemd.mount man page suggests it's the
preferred method, but that may be my misunderstanding. As I said
before, I find the systemd docs a real challenge to read. No doubt they
are correct, but they remind me of something we used to say about the
UNIX man pages back in the 70s: in order to understand one of them, you
just have to read all the other ones first.
2) I've only now noticed that findmnt gives an output line even when
the device is not mounted (the filesystem type is listed as 'autofs').
My fault for not looking more carefully.
Finally, without me doing anything at all except leave the system alone
for a few hours, it has suddenly started working. Go figure.
I now have to work out where to put the ExecStart/Stop lines.
poc