The current KVM Host HA feature depends on the existence of an NFS primary storage to detect which nodes are online, even if other types of primary storage are used. StorPool extends the HA feature to allow other methods to be used for this. The new implementation adds support for using StorPool Storage for HA heartbeats, removing the need for NFS primary storage. The solution developed by StorPool allows new storage vendors and protocols to be added easily. ----------------------------------------- The CloudStack Collaboration Conference 2023 took place on 23-24th November. The conference, arranged by a group of volunteers from the Apache CloudStack Community, took place in the voco hotel, in Porte de Clichy, Paris. It hosted over 350 attendees, with 47 speakers holding technical talks, user stories, new features and integrations presentations and more.

1. 1
Extending KVM Host HA
for Non-NFS Storage
24 Nov 2023

2. 2
Agenda
1. Why we are working on this? - StorPool in a Nutshell
2. KVM Host HA Today
a. How it works with NFS Primary Storage
b. HA Regardless of Storage PR 4978 - Cancelled Project
3. How StorPool extends KVM Host HA
4. Characteristics of KVM Host HA with StorPool
5. Future Possibilities

3. 3
• A leader in hardware agnostic...
• High-performance, highly-reliable, linearly scalable, block-storage software
• 30+ Countries of Deployment on 4 continents
• Production proven and hardened since 2012
• Hundreds of the most demanding deployments
• Self-funded & no VC money
• Profitable and Growing Vendor
• Mission: A Better World through Faster Storage
• StorPool accelerates any Human activity by storing and processing data more
productively
StorPool in a Nutshell

4. 4
How KVM Host HA works with NFS storage
The HA mechanism is elaborate, so we aimed to introduce as few changes as
possible - changing only the agent-side instead of the framework.
Key functions:
Performs heartbeat with the NFS primary storage and takes appropriate actions
with affected resources if the health check fails.

5. 5
Characteristics of KVM Host HA with NFS
1. The cloud depends on the availability of the NFS primary storage.
2. Makes NFS primary storage a mandatory component in a cloud with KVM
host HA enabled, even when another shared storage is available.
3. The HA mechanism does not monitor the health of the primary storage
actually used for VM data if it’s not NFS.

6. 6
How StorPool Extends KVM Host HA
1. Added a modular mechanism to
replace the NFS primary storage
heartbeat dependency
2. Everything else is maintained as
is.

7. 7
1. The storage heartbeat ping test is redirected to monitor StorPool
cluster state.
2. Relies on the StorPool cluster mechanisms to reliably detect that
hosts are online.
KVM Host HA with StorPool Storage

8. 8
Characteristics of KVM Host HA with StorPool
1. Supports disaggregated deployments initially
2. The cloud can depend on the health of the primary storage
actually used for VM data, if it is StorPool Storage.
3. Cloud designs for clouds with KVM host HA can skip NFS primary
storage unless the intention is to use it for VM data.

9. 9
Future Possibilities
1. Add support for HCI deployments with CloudStack compute and StorPool
running concurrently on the same servers.
2. Other storage vendors can implement their own approach in their plugins for
heartbeats using the new modular mechanism to detect that hosts are alive
and connected to the primary storage.

10. 10
The ideal foundation for large-scale clouds running diverse,
mission-critical workloads
Alex Ivanov
Product Lead
ai@storpool.com