Hi, just in addition to the previous response, cinder-volume is a stateful service and there should be only one instance running. We configured it to be bound to the virtual IP controlled by pacemaker, pacemaker also controls all stateless services in our environment although it wouldn't be necessary. But that way we have all resources at one place and don't need to distinguish. Zitat von Satish Patel <satish.txt@gmail.com>:
Hi,
3 nodes requirements come from MySQL galera and RabbitMQ clustering because of quorum requirements ( it should be in odd numbers 1, 3, 5 etc..). Rest of components works without clustering and they live behind HAProxy LB for load sharing and redundancy.
Someone else can add more details here if I missed something.
On Thu, Aug 25, 2022 at 4:05 AM 박경원 <park0kyung0won@dgist.ac.kr> wrote:
Hello
I have two questions about deploying openstack in high available setup
Specifically, HA setup for controller nodes
1. Are openstack services (being deployed on controller nodes) stateless?
Aside from non-openstack packages(galera/mysql, zeromq, ...) for infrastructure, are openstack services stateless?
For example, can I achieve high availability by deploying two nova-api services to two separate controller nodes
by load balacing API calls to them through HAproxy?
Is this(load balancer) the way how openstack achieves high availability?
2. Why minimum 3 controller nodes for HA?
Is this solely due to etcd?
Thanks!