neutron-linuxbridge-agent oslo_service.service amqp.exceptions.InternalError: Connection.open: (541) INTERNAL_ERROR - rabbitmq

Question

Openstack Train version's neutron-linuxbridge-agent component's log show error:
2022-03-17 14:38:36.727 6 ERROR oslo_service.service File "/var/lib/kolla/venv/lib/python3.6/site-packages/amqp/connection.py", line 648, in _on_close
2022-03-17 14:38:36.727 6 ERROR oslo_service.service (class_id, method_id), ConnectionError)
2022-03-17 14:38:36.727 6 ERROR oslo_service.service amqp.exceptions.InternalError: Connection.open: (541) INTERNAL_ERROR - access to vhost '/' refused for user 'openstack': vhost '/' is down
2022-03-17 14:38:36.727 6 ERROR oslo_service.service
2022-03-17 14:38:36.729 6 INFO neutron.plugins.ml2.drivers.agent._common_agent [-] Stopping Linux bridge agent agent.
docker logs neutron_linuxbridge_agent get:
++ /usr/bin/update-alternatives --query iptables
update-alternatives: error: no alternatives for iptables
++ . /usr/local/bin/kolla_neutron_extend_start
+ echo 'Running command: '\''neutron-linuxbridge-agent --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/ml2/ml2_conf.ini'\'''
+ exec neutron-linuxbridge-agent --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/ml2/ml2_conf.ini
Running command: 'neutron-linuxbridge-agent --config-file /etc/neutron/neutron.conf --config-file /etc/neutron/plugins/ml2/ml2_conf.ini'
All openstack network agent list show state are UP, but Alive are XXX.
What's the problem with my cluster, and how could I fixed that? Thanks a lot.
The key server is rabbitmq reference of amqp.exceptions.InternalError, and the rabbit#node-3.log shows:
2022-03-18 06:50:35.270 [error] <0.21119.0> Error on AMQP connection <0.21119.0> (1.1.1.2:12345 -> 1.1.1.3:55672 - neutron-linuxbridge-agent:7:11111111-1111-1111-1111-111111111111, vhost: 'none', user: 'openstack', state: opening), channel 0:
{handshake_error,opening,
{amqp_error,internal_error,
"access to vhost '/' refused for user 'openstack': vhost '/' is down",
'connection.open'}}

Answer 1

While check and login the rabbitmq server site(http://1.1.1.3:15672/), I get this error tip:
rabbitmq virtual host experienced an error on node and may be inaccessible
Solve it by:
1, come in the rabbitmq container, and remove or move out recovery.dets file in directory /var/lib/rabbitmq/mnesia/rabbit#node-3/msg_stores/vhosts/628WB79CIFDYO9LJI6DKMI09L.
2, restart rabbitmq container.
Because of:
In RabbitMQ versions starting with 3.7.0 all messages data is combined in the msg_stores/vhosts directory and stored in a subdirectory per vhost. Each vhost directory is named with a hash and contains a .vhost file with the vhost name, so a specific vhost's message set can be backed up separately.
In RabbitMQ versions prior to 3.7.0 messages are stored in several directories under the node data directory: queues, msg_store_persistent and msg_store_transient. Also there is a recovery.dets file which contains recovery metadata if the node was stopped gracefully.
My whole cluster was reboot by accident, it was recoveried by this method.

Answer 2

if you wanna fix your problem easily please deploy your Rabbimq again with Kolla-ansible.
kolla-ansible -i <INVENTORY> deploy -t rabbitmq -vvvv
it's my experience that the easiest way with the lowest cost of fixing Rabbimq or oslo problem in OpenStack is to redeploy Rabbitmq and invest your time.