Comment 2 for bug 2060395

I scaled back a nova-node with a ovn-dedicated-chassis because I changed the node hostname and the dns resolvers.
The node I scaled back was not also a ceph osd node so I resolved purging al the .deb related to nova and ceph:

apt -y purge nova-common neutron-ovn-metadata-agent neutron-common qemu-system-common qemu-block-extra qemu-system-data qemu-system-gui qemu-system-x86 qemu-utils libvirt-daemon-driver-qemu ipxe-qemu-256k-compat-efi-roms ipxe-qemu libvirt-clients libvirt-daemon-config-network libvirt-daemon-config-nwfilter libvirt-daemon-system-systemd openstack-release python3-openstacksdk python3-oslo.config

rm -fr /var/lib/libvirt /var/lib/neutron/ /var/lib/nova /var/log/nova /var/lib/charm/nova-compute /etc/systemd/system/nova-compute.service.d /etc/nova /var/cache/nova

systemctl unmask nova-compute.service

apt -y purge ceph-common

And then I re-rerun:

juju add-unit nova-compute --to x

now it works