Avi Controller upgrade to 30.2.1 fails due to Insufficient resources at task WaitForAllNodesAfterReboot

Products

• VMware Avi Load Balancer

Issue/Introduction

• Avi Controller upgrade to 30.2.1 fails due to Insufficient resources at task WaitForAllNodesAfterReboot with an error "Insufficient resources. Essentials Controller is deprecated. Minimum memory and CPU supported are 32GB and 6 cores, respectively."
• Upgrade failure is noticed after upgrade status is stuck at 25% for long time.
• An error such as below is noticed when running "show upgrade status detail"

Cause

• The minimum requirement for memory of small Controller is 32 GB. Refer https://techdocs.broadcom.com/us/en/vmware-security-load-balancing/avi-load-balancer/avi-load-balancer/30-2/vmware-avi-load-balancer-installation-guide/preparing-for-installation/nsx-advanced-load-balancer-controller-sizing.html 

Resolution

• Increase memory for each controller node to 32 GB, refer to "Increasing Memory and vCPU of an Avi Load Balancer Controller" section in https://techdocs.broadcom.com/us/en/vmware-security-load-balancing/avi-load-balancer/avi-load-balancer/22-1/vmware-avi-load-balancer-administration-guide/nsx-advanced-load-balancer-controller-operations.html 
• Upgrade the Avi Controller software after increasing the memory to >= 32 GB for each node in the cluster.