[Solved] I have an error in my /etc/fstab file, now I cannot get my rig to boot

[pizzaazzip]

So I was messing with my /etc/fstab file, had a typo and now I can't boot. During the boot process I get a few

Code:

fstab: /etc/fstab:3: Inappropriate file type or format

until it gets to

Code:

ERROR: ABORTING BOOT (sending SIGTERM to parent)!
Dec 5 22:29:26 blade init: /bin/sh on /etc/rc terminated abnormally, going to single user mode
Enter full pathname of shell or RETURN for /bin/sh:

and does not go any further. I found a forum post about freeBSD in general that detailed how to make changes to files in single user mode and have them save but I can't seem to get it to work. Apparently fsck -y does not work in freenas. Anyone have any suggestions on how to save changes to my fstab file? All I need to do is comment that line out for now.

Edit: To fix broken file just hit enter and type nano /conf/base/etc/fstab because I believe /etc/fstab is generated on boot from the /conf/base/etc/fstab file.

 

[jgreco]

"fsck -y" doesn't work in FreeNAS because the boot filesystem is ZFS.

Revert the file back and reboot the system.

 

[pizzaazzip]

"fsck -y" doesn't work in FreeNAS because the boot filesystem is ZFS.

Revert the file back and reboot the system.

could you clarify reverting the file back?

 

[jgreco]

Take the copy of the file that you made before you began adventuring and copy it back to /etc/fstab

 

[pizzaazzip]

Could you explain how to do this? As far as I can tell, single user mode is read only so copying a backup file over is easier said than done.

 

[DrKK]

Can you not boot to an older boot image on the boot device, as a last ditch way to revert?

Also, I suspect I will regret asking this, but I can think of not a single reason on the planet that I would be messing with the appliance's /etc/fstab. Am I perhaps the only one misunderstanding what you're saying? If not, can you tell me what was on your mind when you began to mess with the fstab file?

 

[m0nkey_]

There should be no reason to edit the fstab by hand.

 

[DrKK]

There should be no reason to edit the fstab by hand.

Indeed. I've been sitting here meditating on it for about 20 minutes, and I literally can't think of a reason I'd even WANT to do that, even if I didn't know how bad of an idea it was.

 

[pizzaazzip]

I had a SMB share mounted from another NAS. I rebooted to update and it cleared it so I wanted it to stay. I had it working but I messed with it because the boot process was asking for a password and I could not figure out how to get around that hence the messing. I'm uploading a youtube video to better explain.

 

[jgreco]

Could you explain how to do this? As far as I can tell, single user mode is read only so copying a backup file over is easier said than done.

Remount the filesystem for read-write, of course. "mount -u -o rw /" is what my finger memory says, though for all we know, that might be a SunOS 4 incantation.

 

[pizzaazzip]

still doesn't let me save fstab after I run that

 

[pizzaazzip]

Here is the youtube video. I know it doesn't sound like it in the video, but I really appreciate all of you helping me (I think I sound like a jerk when I'm recording, sorry about that). This is just to make sure we are on the same page

 

[jgreco]

Hmm. Most Youtube doesn't make it very easily thru the UTM here. But I guess the question is, what's the contents of /etc/fstab, and what's actually mounted. I'm not actually that familiar with FreeBSD systems booting from ZFS and where the magic happens in the boot sequence for a ZFS filesystem to mount. So, two things, show us the contents of /etc/fstab

Code:

# cat /etc/fstab

and then also

Code:

# df /

In theory you can twiddle a fs back and forth between rw and ro.

Code:

# df /
Filesystem                                        1K-blocks    Used    Avail Capacity  Mounted on
freenas-boot/ROOT/FreeNAS-9.3-STABLE-201506292332  29232715 1043211 28189503     4%    /
# mount -u -o ro freenas-boot/ROOT/FreeNAS-9.3-STABLE-201506292332 /
# mount -u -o rw freenas-boot/ROOT/FreeNAS-9.3-STABLE-201506292332 /
#

But I don't really know how that interacts with a broken /etc/fstab offhand.

 

[Bidule0hm]

Why not just reinstall the system and upload your saved config? (I hope you backed up your config)

But at the same I'm curious to know how to solve the problem without re-installing :)

 

[DrKK]

Also,

A **VERY** good rule of thumb, when dealing with an **APPLIANCE**, like FreeNAS, versus, **SOFTWARE**, like FreeBSD, is that an APPLIANCE, like other appliances (toasters, laundry machines, dildos) are not meant to be fucked with (well, ok, maybe dildo wasn't the best choice here given this phrasing). Any choices you have will be provided to you with dials, buttons, etc. If you find you have to do something to FreeNAS for which the developers have not provided a "button", or setting, or something, in the GUI, then almost certainly you do *NOT* want to do that, and doing so represents much more risk than benefit (because if it did not, then presumably, we'd give you a button for it.)

 

[Robert Trevellyan]

 

[pizzaazzip]

Yeah, hindsight is 20/20. I've only been using freenas for about a week so I'll make sure next time I mess with the files, I'll backup my configuration. This has all been a learning experience for me. I'll try Jgreco's suggestion tonight. I also wish I could figure how to mount the USB boot drive to another machine and modify it that way. I made a freebsd live CD in hopes for me to modify things that way, i also installed zfs support on both Ubuntu and os x but still wasn't able to figure that out.

 

[m0nkey_]

Disregard, just remembered that /etc is tmpfs and built on the fly at boot.

 

[jgreco]

I'm more curious to see what actually IS in the fstab. I'm an old-time curmudgeon who has spent many hours manually editing partition tables and moving crap around on live production systems since the old SunOS days, and the ZFS auto-magic-mounting stuff leaves a bit of a bad taste in my mouth.

The answer to this might involve specifying an alternative, corrected fstab file (-F) but the interactions with ZFS are new to me.

 

[jgreco]

indeed it's a strange one.

Dude, we don't care what's in YOUR fstab, we want to know what's busted in HIS.