FCOS Getting Started Guide - Error

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1

I am following the libvirt example in the Getting Started Guide for FCOS and getting an error. I am using F39 Workstation as host.

If I use the example using a local install of coreos-installer from F39 repository, and the latest stable version of FCOS, I get the following error (virt-install using qemu:///system):

Proceed with defaults
changing security context of '/home/bgsmith/src-fcos/fc39-1.ign'
Starting install...
Allocating 'fcos-test-01.qcow2'                               |    0 B  00:00:00 ... 
Removing disk 'fcos-test-01.qcow2'                            |    0 B  00:00:00     
ERROR    Cannot access backing file '/home/bgsmith/.local/share/libvirt/images/fedora-coreos-39.20231119.3.0-qemu.x86_64.qcow2' of storage file '/var/lib/libvirt/images/fcos-test-01.qcow2' (as uid:107, gid:107): Permission denied
Domain installation does not appear to have been successful.
If it was, you can restart your domain by running:
  virsh --connect qemu:///system start fcos-test-01
otherwise, please restart your installation.

If I change virt-install to use qemu://session then the example works.

The uid/gid 107 is associated with the system qemu user and group. I verified that selinux labels conform the settings in the Tip.

I would appreciate some ideas on what I am missing. I use libvirt routinely with Vagrant so there must be something I am overlooking.

2 
ERROR    Cannot access backing file '/home/bgsmith/.local/share/libvirt/images/fedora-coreos-39.20231119.3.0-qemu.x86_64.qcow2'

Have you verified that the qemu unprivileged user can access this file?

99% of the time this is a missing x permission for others on your home folder /home/bgsmith:

$ chmod a+x /home/bgsmith
3

Thanks Timothée. Your analysis is on target. At some point in the far (?) distant past I must have done a chmod -R 700 /home/bgsmith as part of a security improvement. I also needed to apply chmod a+x to .local and .local/share as these were also set with 700 permissions.

I may submit a PR to the documentation with an additional note on permissions.

4

Probably not.
I think the users home directory has 0700 permissions by default. That has bitten me in the past as well.