libvirt / qemu guest won’t start

If you see the error message “Error starting domain: Requested operation is not valid: network ‘default’ is not active”, it means the network hasn’t started.

Do the following:

sudo virsh net-list --all

You will see:

sudo virsh net-start default

Network default started

Set it to autostart:

sudo virsh net-autostart default

Check status:

sudo virsh net-list --all