An empty fstab file, at that!

I have an sbc that, as of right now, only mounts one partition. I would like to add a swap partition or file. Normally, I would set up said partition or file and then add it to the fstab.

However, when I go to do so, the current fstab contains the following single line:

# UNCONFIGURED FSTAB FOR BASE SYSTEM

OK, so somehow this debian system knows to mount an SD card partition as '/' without being told to do so in the fstab. So, if I add a new entry for a swap partition/file, will it still know how to mount the root partition, or am I fixing to break something?!?

Thanks!
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on 27 Sep 2019, Dumas Walker said...

I have an sbc that, as of right now, only mounts one partition. I would

^^^^^^^^^^^^^^^^^^^^^^^^^^
...which is running what? Some frankensteinian mutation of debian?

# UNCONFIGURED FSTAB FOR BASE SYSTEM

OK, so this is generally what debootstrap generates -- an empty fstab. Either it has an fstab somewhere in initrd, or it's got one in /lib/init/fstab that contains the partitions that absolutely must be mounted, while /etc/fstab can be used to override those entries.

Ridiculous, isn't it?

OK, so somehow this debian system knows to mount an SD card partition as '/' without being told to do so in the fstab. So, if I add a new entry

It's initrd. I'm calling it.

for a swap partition/file, will it still know how to mount the root partition, or am I fixing to break something?!?

You'll be fine. Just add the swap entry to /etc/fstab. It's not conflicting with anything in any other fstab, right? You don't *currently* have a swap partition on, right? So it's fine.

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I have an sbc that, as of right now, only mounts one partition. I would

^^^^^^^^^^^^^^^^^^^^^^^^^^
...which is running what? Some frankensteinian mutation of debian?

Honestly, I thought it was mostly debian just with a kernel that was
compiled to run on the board (a Galileo Gen 2). However, I am now going
with bastardized debian that was compiled to run on the board BUT that some moron thought should also be compiled to not support such things as
swapspace or nfs.

I think I am justified with the moron assumption... the thing does not have enough physical memory not to need swapspace. It throws a bunch of memory-related errors otherwise.

# UNCONFIGURED FSTAB FOR BASE SYSTEM

Ridiculous, isn't it?

Starting to look that way. :)

As best as I can tell, here have been three attempts at a linux for the
galileo board... the "official" yocto linux that I tried and could never
get to do much of anything, including accept updates; this debian version, based on wheezy; and a version of ubilinux, which is debian based but is apparently no longer available.

I was actually hoping to get ubilinux for it. That is the default linux on
the UP Board that I have and it seems to work quite well. So I figure
their attept for galileo might also be good.

I bought it at about 1/3rd of the price knowing it was no longer supported
by Intel but figuring that it couldn't be too difficult to get linux
running on it with what I would consider fairly bare essentials included
(swap and nfs count as essentials to me <grin>). If I can find the source
for this kernel, I can attempt compiling it although I am not 100% sure
that this bastard linux would support that, since a previous attempt to
compile SBBS ran into the aforementioned errors.

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on 28 Sep 2019, Dumas Walker said...

Honestly, I thought it was mostly debian just with a kernel that was compiled to run on the board (a Galileo Gen 2). However, I am now going with bastardized debian that was compiled to run on the board BUT that some moron thought should also be compiled to not support such things as swapspace or nfs.

And let me guess... they didn't publish the sources anywhere (violating the license in the process)? If not, download the sources and hop into make
config to find out if they really were such massive assholes as to disable
the swap device (which, honestly, I don't even think the kernel config has an option for that, but I haven't been inside there for a while so I'm probably wrong).

Do you at least have a mkswap command? Can you invoke 'swap on'?

--- Mystic BBS v1.12 A43 2019/03/03 (Windows/32)
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