Open Stack

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 at 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 at 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!
>>