1. High Availability

High Availability 的設計會應得抵抗網路攻擊，佮自動偵測、減輕佮修復 vulnerabilties。
Load Balancer 用來 ka 對外口入來的 network traffic 分散予 multiple servers。
𪜶使用不仝款的 scheduling 技術來分散 workload。

• Least Utilized Host
• Affinity
• DNS Round Robin

1.1 Load Balancer Configuration

有兩種 configurations 會當考慮：

• active/active load balancer configuration
• active/passive load balancer configuration

1.2 Clustering

設定 cluster infrastructure ài 了解的重要觀念：

• Active-Passive Node Configuration
• Quorum Disk
• Witness Server
• Heartbeat Communication
• Virtual IP(VIP)

2. Site Considerations

三種型態的 recovery sites：

• Hot Site
• Warm Site
• Cold Site

2.1 Cloud Data Replication

四種不仝款的 storage replication models：

• Local Redundant Storage(LRS)
• Zone Redundant Storage(ZRS)
• GEO Redundant Storage(GRS)
• GEO Zone edundant Storage(GZRS)

2.2 **Data Sovereignty

3. Platform Diversity

Diversity 提供的好處：

• Redundancy
• Adaptability
• Resilience against evolving threats
• Enhanced recovery options
• Compliance and regulation

4. Multi-Cloud Systems

5. Continuity of Operations

6. Capacity Planning

7. Testing

8. Backups

• Important Backup Features

9. Power