fstab no longer mounting nfs shares at boot

[scottbomb]

After years of arm-wrestling with samba, I finally gave up and gave NFS a try, which I think is superior in a pure Linux network like I have now.

The problem is, the shares won't mount at boot, even though they're defined in fstab.

if I wait until the system is done booting, I can execute

sudo mount -a

and the shares from the server mount perfectly. My question is, why won't this work at boot time?

Here's what their lines look like in fstab:

192.168.1.2:/media/Romulus/Television /media/Television nfs defaults,timeo=30,retry=10,auto 0 0
192.168.1.2:/media/Kronos/Movies /media/Movies nfs defaults,timeo=30,retry=10,auto 0 0

And like I said, they mount just fine if I do it manually with mount -a, but they won't mount at boot. It's like systemd is just ignoring the entries. All of my internet searches lead me to results that discuss using systemd to mount them (with various methods that are a bit confusing) but I'd prefer to just keep things simple and do it in fstab like I mount my hard drives.

Any ideas of what I can do to make the system actually mount these at boot time? Is it because network manager isn't running yet? If so, is there something else I need to do to force that first?

[TheFu]

If the NFS mounts are being attempted before networking is up, they will fail. There are mount options to let the mount subsystem (now systemd.mount) know that the mounts need networking first.

I don't mount NFS using the fstab. I use autofs for NFS, Samba and USB storage which mounts those each only on-demand, the umounts them when they are unused. On the nfs server side, there aren't any changes.

On the NFS client side, I use the line below in my auto.nfs config file to mount on disk.

/d/D1 -fstype=nfs,proto=tcp,intr,rw,async  istar:/d/D1

There are 7 nfs mounts in that file.

There is a how-to for autofs somewhere on help.ubuntu.com. Google finds it easily.

[scottbomb]

autofs, I'll check it out, thank you.

[TheFu]

autofs was an option AFTER you added the options to the nfs mounts in the fstab telling it that it is a network device. It was not meant as the first option. Sorry if that wasn't clear. I think it is _netdev as the option, but don't recall exactly. Check the manpages.

       _netdev
              The filesystem resides on a device that requires network  access
              (used  to  prevent  the  system  from  attempting to mount these
              filesystems until the network has been enabled on the system).

that's from the mount manpage.

[scottbomb]

I tried autofs (before reading the previous post) and found it frustrating. I'd really rather just keep using fstab and nfs as normal. Perhaps I can just make a cronjob to run mount -a after a full boot. I guess we can thank systemd for not loading networking before reading fstab?

[TheFu]

There's only 2 tricks to autofs.

The auto.master controls the top level directory for each sub-file which holds the configs.
If you use an auto.master like this:

/-      /etc/auto.nfs

Then the configs inside /etc/auto.nfs specify the full path. That's what the /- does.

The other trick is never, ever, ever, mix directories where autofs manages mounts and where other mounting systems manage mounts .... so don't use /mnt/ or /media/ for autofs stuff. I don't know if this is still an issue or not.

But if this stuff isn't working, I suspect there's something else wrong on the system, somehow. Only looking through the log files will lead to an answer. NFS sorta "just works." When it doesn't, there's a dependency issue or a startup order problem. There is a specific order that rpc and mount and nfs each need to start for things to work. I always have to look those up if there's an issue. Happened in the 1990s and happened again a few months ago on a 16.04 client box here. A reboot didn't fix it. At the time, I was screwing around with internal DNS and thought that was the issue. I wasn't using FQDN and the DNS server was always returning the FQDN for any requests. It was a pain. Then the stars aligned and it worked again. 1 issue in 20+ yrs, not bad.

[Tadaen_Sylvermane]

Use systemd automount? Stays in the fstab. I had a bunch of difficulty with autofs, after awhile it just didn't work. Hung on shutdowns / reboots.

/nfs/share /local/mount nfs defaults,noauto,x-systemd.automount,x-systemd.idle-timeout=30 0 0

This is the template line I use for my nfs shares and my snapraid usb parity drives.

[SeijiSensei]

I was just about to make the same suggestion. My fstab entries include _netdev in the options list.

server:/home /media/server nfs noauto,x-systemd.automount,x-systemd.mount-timeout=30,_netdev   0 0

The mount man page has this description of the _netdev option:

_netdev
The filesystem resides on a device that requires network access (used to prevent the system from attempting to mount these filesystems until the network has been enabled on the system).

[TheFu]

Use systemd automount? Stays in the fstab. I had a bunch of difficulty with autofs, after awhile it just didn't work. Hung on shutdowns / reboots.

/nfs/share /local/mount nfs defaults,noauto,x-systemd.automount,x-systemd.idle-timeout=30 0 0

This is the template line I use for my nfs shares and my snapraid usb parity drives.

I played with x-systemd.automount and it seemed to work, but it never umounted the mount, which bothered me. When I take a laptop off the home network, I'd like not to worry whether it had NFS mounted something 3 days earlier. With autofs, if the file system hasn't been used in about 5 minutes, it gets umount'ed.

[scottbomb]

Nothing I've tried works. It's odd because my laptop seems to boot just fine with access to the NFS shares using the exact same fstab options as the computer having the problem. Every time I reboot it, I have to open a command prompt and do sudo mount -a in order to mount the nfs shares. Here's how it reads now:

192.168.1.2:/media/Romulus/Television /media/Television nfs defaults,nofail,x-systemd.after=network-online.target,_netdev 0 2
192.168.1.2:/media/Kronos/Movies /media/Movies nfs defaults,nofail,x-systemd.after=network-online.target,_netdev 0 2
192.168.1.2:/media/Kronos/ownCloud/Music /media/Music nfs defaults,nofail,x-systemd.after=network-online.target,_netdev 0 2

Systemd doesn't seem to care if the network is up or not, it just ignores these lines, every time. My workaround, when I get around to it, is to have mount -a run after the desktop loads (this PC automatically logs into a desktop session). I know Kubuntu has a place for me to put startup applications but don't know if it will run something as root. If not, I'll have to find some other way. There's a cronjob to run something at startup but I've never gotten that to work, either.

Ain't systemd great? How did we ever get along without it?