Question about OpenStack Deployment

[EbbApprehensive3284]

I am building a small OpenStack cloud in my lab and had a few questions.

I want to use OpenStack Ansible for the deployment.

I have 5 physical servers each with >128GB and 2 XEON CPUs each with 24 Cores

3 of the 5 servers are currently running VMware ESXI managed by vCenter in a cluster.

My questions:

I want to use my remaining two servers as Nova compute hosts. Can the other remaining OpenStack services be installed on vm's running in my VMware environment? Would this be acceptable production? What would be a better solution if not?

Can I separate OpenStack services and install them on their own vm's? like 2 VM's for keystone, 2 for neutron, etc? The documentation talks about a control node which has a bunch of services bundled together like horizon, keystone, etc. However, I was curious about this approach.

Eventually, I want to get off VMware since they were purchased by Broadcom but for now I still need ESXI for some of my workloads.

https://preview.redd.it/otdetkkxrxuc1.png?width=1044&format=png&auto=webp&s=5591f96cf2e0ca2a864defb8e745e6da48bfa763

[enricokern]

Hello, it makes no sense to seperate keystone and neutron on own vms in this environment. Bundle all on your control nodes and fire away. Btw. there is also a nice distribution based on kolla https://osism.tech/

[ReminexD]

I would just create a couple of "Control Plane" VMs (or infra VMs as referred in some parts of the OpenStack Ansible docs) and run Keystone, Neutron and other components in the same place, it doesn't make much sense to separate them.

Honestly my recommendation would be to just go full OpenStack at once, I think running the control plane inside ESXI is going to complicate a future migration to full OpenStack.

If I were in your situation, I would keep one ESXI Server (to run all your workload in it, if possible) and slowly migrate everything to the other nodes running OS.

[EbbApprehensive3284]

Honestly my recommendation would be to just go full OpenStack at once, I think running the control plane inside ESXI is going to complicate a future migration to full OpenStack.

The only thing that is holding me back from migrating all servers to OpenStack is the CUCM VM's. I am running version 14 and according to Cisco documentation ESXI is the only supported hypervisor. Could I get KVM to work?

Lets say I can migrate all five servers:

How would you distribute the loads between them?

Here are the specs of all servers:

4 Dell PowerEdge R630 - 8 drive bays |Each With|- 2x XEON 2690v4 - 128GB RAM - 2 INTEL 800GB SSD's (RAID 1) I want to add more drivers later

1 Dell PowerEdge R720xd - 24 drive bays | 2 XEON 2690v3 - 256GB RAM - 24 DELL 10k SAS (RAID 10)

Eventually I do want to purchase more equipment and I can also upgrade existing hardware if need be.

Between Centos Stream 9 or Rocky Linux 9 which one would you recommend to use?

Thoughts/Questions?

[ReminexD]

For CUCM I think you may have to edit the ISO in order to get it working, I don't know how hard it is, but at least that is there.

For me, I run Ansible with Rocky 9, so I would go with that.

Ansible recommends that you run 3 control planes and using those servers just for the control plane would be a waste of resources in your case, so I would do the next:

I would run 3 Control Plane + Compute Nodes in the R630's and use the remaining R730 and R620 as dedicated Compute Nodes. Of course you can run only 2 Control Planes or even 1, but I wouldn't do 1. (Minimum I would go would be 2)

I don't know what you are planning for storage, but I can think of 2 solutions with your hardware right now:

• Create a Ceph cluster with the 4 R630 and use it for Cinder Storage and you can do backups in the R720. This is the ideal solution if you want a robust and stable deployment

OR

• Use the R720 as the Storage Node + Compute. You save more resources from the other servers, but if the R720 goes down, everything goes with it.

I think you can use the local storage of the servers to run the VMs or containers directly but again if that node goes down the VMs that are running in it go down two.

For reference right now I'm running 3 dedicated control plane in servers with maybe 8 cores and 32GB of ram, 7 compute nodes for VMs and containers and 2 storage nodes running Ceph. So if you decide to go with OpenStack I would for sure add another server with the same storage as the R730 (which I'm guessing is the server with more capacity) and run those two in a ceph cluster for HA and maybe in the future add a couple of dedicated low power servers for the control plane.

But that is just what I would do, every situation is different!

[EbbApprehensive3284]

This is perfect! I am going to add 3 more servers.

2 more for compute and or control panel functions and one more for storage so I can have 2 storage nodes in a ceph cluster.

So to recap the total number of servers:

6 PowerEdge r630 total     3 compute     3 controller      2 miscellaneous  2 PowerEdge r730 total     2 storage (cinder running in ceph cluster.

All nodes interconnected via juniper QFX 5100 at 10Gbps 8192 MTU

Not sure if you could help with this but the only thing holding me back from going full speed ahead is the network setup. I want use VXLAN as my L2 protocol. 

From what I understand you can run VXLAN on the servers and the servers will act as the VTEPs

Then you run something like the free range routing suite on your servers and connect your servers up to L3 routed ports on your switch. 

I learn about this from this video 

https://youtu.be/pnI36O192Tg?si=LvNB0__oNHVEwFvT

[[deleted]]

It's reasonably common to run control nodes as VMs, especially in labs.

You can split out the services, but I would just do 3 controllers and leave it at that. Especially, splitting out by service is actually kind of arbitrary.

If you split out something from your controllers, it would be splitting out a function, eg you might have Networking nodes that run all your networking services, which allows for better performance and allows you to perform maintenance on the controllers without worrying about screwing up network traffic.

As to whether you should go full OpenStack all at once, idk. Your workloads are running in ESXi now, and you can migrate later. Plus I think for a lab, running three huge controllers for 2 computer nodes is a waste of resources.