Aria Automation (formerly vRealize Automation) is designed to automate the deployment of applications and infrastructure across hybrid cloud environments. It enables the provisioning, management, and orchestration of IT services, helping organizations streamline their service delivery.

Secure Boot uses digital signatures to verify the integrity of the ESXi boot loader and kernel modules.
Lockdown Mode restricts remote access, TPM integration stores cryptographic keys, and vSphere Encryption secures VM data at rest, not the boot process itself.

To enable HA, you must select the "Turn On vSphere HA" option and configure admission control policies as needed. EVC is for CPU compatibility; fault tolerance logging is separate; and while an HA network is recommended, you don't necessarily need a separate vSwitch at creation time.

Aria Operations (formerly known as vRealize Operations) is used to monitor, analyze, and manage the performance of cloud infrastructures, providing insights into capacity, utilization, and overall health. It helps in optimizing resources, preventing downtime, and ensuring the smooth running of applications and services in a VMware environment.

Creating Resource Pools with higher Shares (or reservations) for critical workloads ensures those VMs are prioritized when CPU and memory resources are contended.