Unknown filesystem 'squashfs' on Fedora 30

1

I’m following these instructions to be able to install snaps on fedora:

https://snapcraft.io/docs/installing-snap-on-fedora

But when I try to install the hello-world snap (or any snap) I get the following error:

error: system does not fully support snapd: cannot mount squashfs image using "squashfs": mount:
       /tmp/sanity-mountpoint-988430154: unknown filesystem type 'squashfs'.

This has happened to me on a fresh AWS instance and on a fresh VM with multipass.

Is there any workaround for this?

2

It looks like the squashfs filesystem is compiled as a module in Fedora, so you need to check whether it has been loaded into the kernel with something like lsmod. If it isn’t loaded you can load it by running modprobe squashfs. I don’t know whether snapd is capable of loading the module itself or if it even needs to, nor do I know how to ensure that the module is otherwise loaded when you want to use it in fedora.

3

Installing snapd from the repo should have pulled kernel-modules package. Unless you’ve hit https://bugzilla.redhat.com/show_bug.cgi?id=1652823 in which case dnf incorrectly pulls the debug kernel and a corresponding modules package.

Please make sure that kernel-modules is installed, if not dnf install kernel-modules -y should do the trick.

4

Yes, it seems like kernel-modules wasn’t installed correctly. Nonetheless I’m still having the same issues, and when I tried to modprobe squashfs it seemed to not find any module.

5

Another edge case, IIRC when you dnf install kernel-modules it installs the modules for the latest kernel version (and potentially pulls in the kernel). Can you check there’s a kernel-modules version matching your kernel installed? Trying rpm -qa kernel\* | sort should provide some insight.

6

Seems like there isn’t:

[multipass@aroused-pintail ~]$ rpm -qa kernel\*
kernel-debug-core-5.2.17-200.fc30.x86_64
kernel-modules-5.2.17-200.fc30.x86_64
kernel-debug-modules-5.2.17-200.fc30.x86_64
kernel-core-5.2.17-200.fc30.x86_64
kernel-core-5.0.9-301.fc30.x86_64
[multipass@aroused-pintail ~]$ uname -a
Linux aroused-pintail 5.0.9-301.fc30.x86_64 #1 SMP Tue Apr 23 23:57:35 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
7

Yeah, rebooting should help you get going.

2 Likes
8

That did the job, thanks!

2 Likes
9

Awesome, I’m really happy that @mborzecki got you going :slight_smile: