Hello everyone. I want to summary for who meets problems with Openstack when deploy cluster with 3 controller using Kolla Ansible Scenario: 1 of 3 controller is down 1. Login horizon and use API such as nova, cinder will be very slow fix by: nano: kolla-ansible/ansible/roles/heat/templates/heat.conf.j2 kolla-ansible/ansible/roles/nova/templates/nova.conf.j2 kolla-ansible/ansible/roles/keystone/templates/keystone.conf.j2 kolla-ansible/ansible/roles/neutron/templates/neutron.conf.j2 kolla-ansible/ansible/roles/cinder/templates/cinder.conf.j2 or which service need caches add as below [cache] backend = oslo_cache.memcache_pool enabled = True memcache_servers = {{ kolla_internal_vip_address }}:{{ memcached_port }} memcache_dead_retry = 0.25 memcache_socket_timeout = 900 https://review.opendev.org/c/openstack/kolla-ansible/+/849487 but it is not the end 2. Cannot launch instance or mapping block device(stuck at this step) nano kolla-ansible/ansible/roles/rabbitmq/templates/definitions.json.j2 "policies":[ {"vhost": "/", "name": "ha-all", "pattern": "^(?!(amq\.)|(.*_fanout_)|(reply_)).*", "apply-to": "all", "definition": {"ha-mode":"all"}, "priority":0}{% if project_name == 'outward_rabbitmq' %}, {"vhost": "{{ murano_agent_rabbitmq_vhost }}", "name": "ha-all", "pattern": ".*", "apply-to": "all", "definition": {"ha-mode":"all"}, "priority":0} {% endif %} ] nano /etc/kollla/global.conf [oslo_messaging_rabbit] kombu_reconnect_delay=0.5 https://bugs.launchpad.net/oslo.messaging/+bug/1993149 https://docs.openstack.org/large-scale/journey/configure/rabbitmq.html I used Xena 13.4 and Yoga 14.8.1. Above bugs are critical, but I see that it was not fixed. I am just an operator and I want to share what I encountered for new people who come to Openstack Nguyen Huu Khoi