红帽全球峰会10.6. Control plane resiliency and recovery
You can use the control plane machine set to improve the resiliency of the control plane for your OpenShift Container Platform cluster.
When possible, the control plane machine set spreads the control plane machines across multiple failure domains. This configuration provides high availability and fault tolerance within the control plane. This strategy can help protect the control plane when issues arise within the infrastructure provider.
Review failure domain support for your cloud provider to determine how to configure high availability for your control plane.
| Cloud provider | Support for failure domains | Provider nomenclature |
|---|---|---|
| Amazon Web Services (AWS) | X | |
| Google Cloud | X | |
| Microsoft Azure | X | |
| Nutanix | X | |
| Red Hat OpenStack Platform (RHOSP) | X | OpenStack Nova availability zones and OpenStack Cinder availability zones |
| VMware vSphere | X | failure domain mapped to a vSphere Zone [1] |
- For more information, see "Regions and zones for a VMware vCenter".
The failure domain configuration in the control plane machine set custom resource (CR) is platform-specific. For more information about failure domain parameters in the CR, see the sample failure domain configuration for your provider.
10.6.1.2. Balancing control plane machines
The control plane machine set balances control plane machines across failure domains to ensure fault tolerance and high availability.
When possible, the control plane machine set uses each failure domain equally to ensure appropriate fault tolerance. If there are fewer failure domains than control plane machines, failure domains are selected for reuse alphabetically by name. For clusters with no failure domains specified, all control plane machines are placed within a single failure domain.
Some changes to the failure domain configuration cause the control plane machine set to rebalance the control plane machines. For example, if you add failure domains to a cluster with fewer failure domains than control plane machines, the control plane machine set rebalances the machines across all available failure domains.
'%20d='M201.5%20305.5c-13.8%200-24.9-11.1-24.9-24.6%200-13.8%2011.1-24.9%2024.9-24.9%2013.6%200%2024.6%2011.1%2024.6%2024.9%200%2013.6-11.1%2024.6-24.6%2024.6zM504%20256c0%20137-111%20248-248%20248S8%20393%208%20256%20119%208%20256%208s248%20111%20248%20248zm-132.3-41.2c-9.4%200-17.7%203.9-23.8%2010-22.4-15.5-52.6-25.5-86.1-26.6l17.4-78.3%2055.4%2012.5c0%2013.6%2011.1%2024.6%2024.6%2024.6%2013.8%200%2024.9-11.3%2024.9-24.9s-11.1-24.9-24.9-24.9c-9.7%200-18%205.8-22.1%2013.8l-61.2-13.6c-3-.8-6.1%201.4-6.9%204.4l-19.1%2086.4c-33.2%201.4-63.1%2011.3-85.5%2026.8-6.1-6.4-14.7-10.2-24.1-10.2-34.9%200-46.3%2046.9-14.4%2062.8-1.1%205-1.7%2010.2-1.7%2015.5%200%2052.6%2059.2%2095.2%20132%2095.2%2073.1%200%20132.3-42.6%20132.3-95.2%200-5.3-.6-10.8-1.9-15.8%2031.3-16%2019.8-62.5-14.9-62.5zM302.8%20331c-18.2%2018.2-76.1%2017.9-93.6%200-2.2-2.2-6.1-2.2-8.3%200-2.5%202.5-2.5%206.4%200%208.6%2022.8%2022.8%2087.3%2022.8%20110.2%200%202.5-2.2%202.5-6.1%200-8.6-2.2-2.2-6.1-2.2-8.3%200zm7.7-75c-13.6%200-24.6%2011.1-24.6%2024.9%200%2013.6%2011.1%2024.6%2024.6%2024.6%2013.8%200%2024.9-11.1%2024.9-24.6%200-13.8-11-24.9-24.9-24.9z'/%3e%3c/svg%3e){kind=small}