Can One Add a Second Master Node to an Already Configured Single Master Node Cluster?

Problem

Cluster is running with only 1 master and 3 workers nodes. Is it possible to add another Master Node to this cluster?

Environment

• Platform9 Managed Kubernetes - All Versions
• BareOS

Answer

• You cannot add more master nodes to a cluster that's created with a single master node today without having a VIP (Virtual IP Address) associated to it. If cluster is created via U/I, this is achieved when using the One-Click Cluster or Single Master Cluster workflow.

• You can scale up/down master nodes in a cluster having a single master node if it was created via U/I with the Multi-Master Cluster workflow where a VIP was provided at cluster creation time.

Additional Information

• Multimaster Architecture Platform9 Managed Kubernetes
• If cluster is created using API, the masterVipIpv4 and masterVipIface options will need to be passed to enable the option to scale master nodes later.
• Idea: PMK8-I-260