ovn-central unit lists non-existent Chassis host

[Peter Matulis]

An initial deploy of OVN yielded a single ovn-chassis residing on machine

virt-node-06.maas

Scaling out the nova-compute application gave an additional ovn-chassis on machine

virt-node-01.maas

After removing the first nova-compute unit the ovn-central unit continues to list the non-existent Chassis host:

$ juju run --unit ovn-central/0 'ovn-nbctl show'

This is the router entry:

router b286d2ee-2d71-4bee-a737-1bddb294f8c1 (neutron-136ca85e-751a-4573-a4fb-013d0701bb5a) (aka router1)
    port lrp-3eadbdf8-7425-49f9-8859-0e35fff423ba
        mac: "fa:16:3e:ca:2c:4a"
        networks: ["192.168.0.1/24"]
    port lrp-b0fe3bcf-40d7-42b8-b503-9210380ade86
        mac: "fa:16:3e:9c:4b:34"
        networks: ["10.246.116.4/21"]
        gateway chassis: [virt-node-06.maas virt-node-01.maas]
    nat 77578e9a-da83-4c1a-86e4-869edd0989eb
        external ip: "10.246.116.4"
        logical ip: "192.168.0.0/24"
        type: "snat"
    nat c059c8de-3845-469b-a169-24e7d4d81742
        external ip: "10.246.116.0"
        logical ip: "192.168.0.23"
        type: "dnat_and_snat"

This is what Juju shows at this time:

$ juju status nova-compute

App Version Status Scale Charm Channel Rev Exposed Message
nova-compute 25.0.0 active 1 nova-compute yoga/stable 588 no Unit is ready
ovn-chassis 22.03.0 active 1 ovn-chassis 22.03/stable 46 no Unit is ready

Unit Workload Agent Machine Public address Ports Message
nova-compute/1* active idle 3 10.246.114.100 Unit is ready
  ovn-chassis/1* active idle 10.246.114.100 Unit is ready

Machine State DNS Inst id Series AZ Message
3 started 10.246.114.100 virt-node-01 focal default Deployed

Instances continue to be routed to properly.