A hybrid model using Subscription for predictable base load provides cost savings for always-on components, while Pay-As-You-Go for scaling handles unpredictable surges perfectly. This balances performance guarantees with optimal cost-efficiency for variable workloads.

Lifecycle rules automatically transition objects to cheaper storage classes (like IA or Archive) after a set period, which is the core solution for managing archival data costs. Simply changing the class of existing objects manually (B) is not scalable. Versioning (A) and increased redundancy (D) would increase, not decrease, costs.

RDS instances have a security feature called an IP whitelist (or security group for RDS) that explicitly defines which source IPs can connect. Even within the same VPC, if the ECS instance’s private IP is not in the whitelist, connections will be rejected. This is a common and easily overlooked configuration step.

For disaster recovery (DR) across regions with fast failover and minimal data loss (RPO), DTS provides continuous, real-time data synchronization. This creates a hot standby in another region. Cross-region backups (C) are for backup recovery, not fast failover. A cross-zone instance pair (D) protects against zone failure, not regional disaster. Manual snapshots (A) involve significant data loss and manual intervention.

Cost Center (formerly User Center > Cost Billing) is the dedicated service for financial management, offering cost analysis, budgeting, invoicing, and detailed reports that can be filtered and grouped by resource tags, projects, services, and instances.

A short cooldown period allows new scaling evaluations before the previous scaling action’s effects (like load distribution) are fully realized, causing thrashing. Increasing the cooldown period gives the system time to stabilize after a scaling action, preventing rapid, cyclical scaling decisions.

Creating a snapshot of the disk captures its exact state at a point in time. Snapshots are stored independently in OSS and are much cheaper than maintaining a full instance or custom image. You can later create a new disk from this snapshot if you need to access the files.

A NAT Gateway allows instances in a private VPC subnet to initiate outbound connections to the internet (e.g., for updates) while preventing unsolicited inbound connections from the internet. This is a secure, permanent, and scalable architecture that adheres to the ‘no public IP’ policy.

Unattached EIPs and unassociated Pay-As-You-Go data disks incur hourly charges. They are billable resources independent of any instance. Best practice is to release them promptly to avoid unnecessary costs. Subscription resources are different and may be retained for future use.

A hybrid model using Subscription for predictable base load provides cost savings for always-on components, while Pay-As-You-Go for scaling handles unpredictable surges perfectly. This balances performance guarantees with optimal cost-efficiency for variable workloads.0