On Thu, Jul 9, 2020 at 4:25 AM Anil Jangam <anilj.mailing@gmail.com> wrote:
Hi All,
I am looking for hardware requirements (CPU, RAM, HDD) for installing a OpenStack HA cluster. So far, I gathered few references:
- This article talks about CPU and HDD, but they do not comment on RAM. - https://docs.openstack.org/project-deploy-guide/openstack-ansible/ocata/over... - This article talks about CPU, RAM, and HDD, but it is quite old (2015) reference. - https://docs.huihoo.com/openstack/docs.openstack.org/ha-guide/HAGuide.pdf (Page 6)
I am considering the cluster with: 3 Controller (for HA) + 1 Compute + 1 Storage.
I have following questions:
- What is the minimum hardware (CPU, RAM, HDD) requirement to install a OpenStack HA cluster?
For memory, you could probably get away with 16 GB on the controllers, but I would go at least 32. I have 64 in mine. My lightly loaded dev cluster sits at about 15GB used under light load.
For a small cluster, I wouldn't go less than 4 cores. A single 8 core CPU will be plenty. If you think you're going to grow it and make heavy use of the APIs then double it. For HDD, you can get away with like 100 GB or even less, but you need to account for your Glance images assuming you're storing them locally. You'll also need space for logging if you're going ot deploy an ELK (or EFK) stack with it. Databases are fairly small. In a cluster with only a few compute nodes, they probably will be around 5 or 6 GB total. If you can throw a 1TB SSD at it, that should be plenty for a small cluster.
- Can we have 3 Controller nodes installed on 3 Virtual Machines or do we need 3 independent (bare metal) servers? - So in case of VM-based controllers, the cluster will be hybrid in nature. - I do not know if this is even possible and a recommended design.
I guess it depends on your threshold for failure. It seems to me to defeat
the purpose of HA to stick everything on one physical box. It's certainly fine for testing / demonstration purposes. Is it supported? Sure. Is it recommended? No.
- - Do we need the Platform Director node in addition to controller and compute/storage nodes?
I am not familiar with OSA enough to say for sure, but I don't think so.
You should be able to deploy with 'localhost' in your inventory as one of your controllers. You can also simply run the deployment from a linux VM on a laptop if you want. You shouldn't have to dedicate something. That being said, if you have a box where those things can live and be used repeatedly for reconfiguration and upgrade, it would probably make your life less complicated.
Thanks in advance. Anil.
-Erik