AWS 學習筆記 (五) : AWS Cloud Economics 課程筆記

搞定 Business 與 Technical Professional 課程後, 繼續向 Cloud Economics 進軍, 網址如下 (需登入 APN 帳號) :

# AWS Cloud Economics (Digital : 編號 35616)

這個對我而言是很陌生的課題, 但卻是客戶最關心的議題. 為何要談經濟學問題呢? 這是因為要讓客戶充分了解遷移到 AWS 會帶來多少商業價值而產生信心, 透過可預期之成本節降效果來贏得客戶信任, 原文如下 :

"Giving customers confidence that migrating to AWS brings known and defined business value. Earn customer trust through proactive cost redunction and optimized strategies."

除了成本節降外, 最重要的是要讓客戶了解 AWS 可以帶來企業效能 (business performance) 與客戶體驗 (customer experience) 方面的提升.


module 1 : introduction to business value

雲端經濟學的兩個主要領域 :

• business value (商業價值) : TCO 
• cloud financial management (雲端金融管理)

雲端價值框架 (Cloud Value Framework) 的四個支柱 (pillars) :

• Cost savings (TCO) (成本節降) : 約 51% 節降效果
• Staff productivity (員工生產力) : 約增加 62% 
• Operational resilience (營運彈性) : 降低 downtime 約 32%
• Business agility (商業反應) : 迅速建立新市場帶進新營收

客戶一般只關心到成本節降 (因為它顯而易見), 而沒有注意到後面三項較不具體的效益, 但這三項卻是上雲所帶來的真正潛在利益, 也是上雲最具說服力之優點 (most compelling cloud benefits).


Module 2: Cost Savings

主要是比較地端 (on-premises) 與 AWS 雲端的成本差異. 最大的挑戰是如何估算傳統地端配置 (on-premises) 所需的成本. 一般而言在 AWS 上配置之計算核心至少比地端少 20~40%, 而且因為 AWS 已達成經濟規模而形成正循環, 所以上雲的成本還會不斷下降.

AWS 用來節降成本的三種模型 :

• consumption-based model
• AWS pricing model
• frequent price reduction (自動的且一體適用)

傳統地端配置的缺點 :

• over-provision : 配置過度 (閒置與浪費)
• under-provision : 配置不足 (阻礙業務擴張)

AWS 讓客戶在需要擴充時迅速配置所需要的設施. 基本的 AWS 配置如下 :

AWS 的四個 pricing model :

• on-demand
• reserved
• spot
• dedicated 

遷移到 AWS 的成本 (加起來等於 ROI=Return Of Investment) :

• sunk cost=depreciation + recovery value
• migration cost 

遷移到 AWS 可能面對來自 IT 部門的抵制 : 擔心失去工作與專業性.

與客戶討論成本節降時的不要只談價格與折扣, 卻不談成本分析 (cost analysis), 只有透過成本分析才能讓客戶了解地端配置所占的隱形成本有多大.


module 3 : staff productivity

六種主要的 IT 工作項目 :

• Server
• Network
• Storage
• Applications
• Facilities
• Securities

遷移到 AWS 後, 有些工作的子項目整個交給 AWS 而完全消失, 有的則減低了工作量.


module 4 : operational resilience (營運彈性)

營運彈性是指 more uptime 與 security 所帶來的高度可用性 (availability).

operational resilience 的四個基石 :

• operations
• security
• software
• infrastructure

每一個 AWS 計算實體 (instance) 都有兩個獨立的電源供電.


module 5 : Business Agility

此模組介紹 AWS 所帶來的業務敏捷 (business agility) 效益, 以及要用那些 KPI (Key Performance Indicator) 指標來衡量. Business agility 可激發創新 (innovation), 並降低企業運營成本與風險 (decrease the cost and risk).

Business agility means : responding faster, experimenting more, and delivering results in the same or less amount of time. Business agility allows customers to innovate by increasing "fail fast" while reducing risks and costs.

Fail fast : being easily to shut down failed initiatives without the pain and wasted resources associated with an inflexible on-premises environment.

衡量業務敏捷的主要 KPI :

• Time to market for new applications (單位: 月)
• Features per release (單位 : 件數)
• Value per release (application revenue per release)

MTTR (Mean Time To Recover) : 平均恢復時間


module 6 : cloud financial management 

AWS 用戶只支付他們所使用的資源 (pay what they use).

AWS 雲端財務管理的四個領域 :

• measurement and accountability (成本結構透明可稽核)
• cost optimization (根據使用需求動態調整架構)
• planning and forecasting (根據目前與未來 IT 需求)
• cloud financial operations (可自動化)

AWS 讓成本透明化的方法 : 使用 cost allocation tag

成本優化的最佳作法 :

• right-sizing instances (選擇符合效能需求之最便宜 instance)
• increasing elasticity (關閉沒有生產力的 instance, 例如測試或開發用的)
• choosing the right pricing model (使用 reserved instances)
• optimizing storage

Automated Scheduling=Lambda + CloudWatch

監管成本的三種作法 :

• DIY 一個客製化的儀錶板 dashboard
• 使用 APN
• 使用 AWS Cost Explorer (免費的)

可用 CloudWatch 來檢視 instance 的 CPU, menory 的使用情形, 也可以用 Cost Explorer 來尋找可節降成本之機會.

Capacity reservation 的限制 :

• zonal RI 帳單折扣不適用於 capacity reservation
• 不可在 placement group 中建立 capacity reservation
• capacity reservation 不能用在 dedicated host

AWS EC2 的購買選項 :

• on-demand instances (無需長期契約, 用於不可預期負載)
• reserved instances (需 1~3 年契約, 用於可預期負載)
• spot instances (無狀態的閒置容量, 用於不可預期負載, 可達 90% 折扣)

AWS 上的服務中斷 (interruption) : 過去三個月 95% 的 instances 不曾發生中斷.

spot instances 適合用在 (最好放在 container 中) :

• Fault tolerant
• Flexible
• Loosely coupled
• Sateless workload

自動化在 AWS 是很重要的一個功能, 特別是用在成本節降上, 例如 :

• 區別 always-on instances 與建議購買 reserved instances
• 找出應該要瘦身 (downsize) 的 instances
• 自動關閉閒置的 instances 與 EBS 空間
• 自動將資料送到養老院 (aging), 從較貴的 S3 搬到 S3-IA 與 Glacier
• 自動將狀態更新到儀表板上
• 自動產生成本節降報告

module 7 : Introduction to Migration Portfolio Assessment (MPA)

此模組介紹 MPA 工具及其功能. MPA 是一個網頁應用程式, 用來使遷移到 AWS 的進程自動化, 協助客戶驗證 AWS 遷移案以及建立遷移計畫.

誰可以用 MPA 工具?

• Sales team
• Consultants (僅限 Advanced 與 Premier APN 顧問夥伴可用)

MPA 用來進行 Migration 準備, 評估 Cloud business value, 以及做 Cost analysis.


module 8 : Cost savings with MPA

此模組介紹如何在 MPA 工具網站建立一個 portfolio, 匯入, 更新, 刪除, 以及新增資料, 以及執行成本節降分析.


2020-03-21 補充 :

今天是周六, 花了一個早上看完 module 6~8, 吃過午飯後考試, 共 21 題, 一樣是 80% 及格, 我一次 90% 過關 :

AWS 雲端經濟學的考試又跟第一堂的 Business Professional 一樣了, 就是要考完才知道成績, 而且不會告訴你答案與錯在哪裡. 我這次抽到的題目與答題如下 (90% 應該是錯兩題, 還沒檢查是哪兩題) :


1. All of the following are pillars of the Cloud Value Framework except which ones? Select all that apply.

ANS: (1) Security
      (2)

2. Match each pillar of the Cloud Value Framework with its description

ANS: (1) Cost savings - the financial benefits of moving to the cloud
     (2) Staff productivity - the efficiency gained from reducing or eliminating tasks no longer needed with the cloud
     (3) Opertional resilience - the benefit from improved availability and security
     (4) Business Agility - being able to respond faster an experiment more

3. Cloud Economics = ________ + ________.

ANS: Business value + Cloud Financial Management

4. Which kind of analysis calculates the total cost of ownership for running and end-to-end traditional IT environment versus deploying to AWS?

ANS: Cost savings

5. True or False:

A cost savings analysis provides a complete view of costs to deliver equal or improved performance with AWS when compared to an on-premises or co-location infrastructure.

ANS: True

6. AWS helps customers lower costs with (select all that apply):

ANS: (1) consumption-based model
     (2) AWS pricing model
     (3) frequent price reduction

7. Which of the following are common migration challenges for customers discussed in this course? Select all that apply.

ANS: (1) migration-related cost
     (2) shifting to an operational expenditure(OPEX) model
     (3) lack of cloud readiness
     (4) entrenched IT organization

8. _________ refers to the efficiency gained from reducing or eliminating tasks no longer needed with cloud services

ANS: Staff productivity

9. Match the IT staff category with the typical IT-related functions.

ANS: (1) Server, network, and storage - involves managing hardware infrastructure
     (2) Application - roles such as database administrators, ppDev, QA, and support functions
     (3) Facilities - facilities management for customers who have an on-premises data center
     (4) Security - ensures infrastructure meets compliance, regulatory, and corporate standards

10. _______ is the benefit from gained and improved availability and security.

ANS: Operational resilience

11. Identify the four cornerstones of operational resilience discussed in this course. Select all that apply.

ANS: (1) Operations
     (2) Security
     (3) Software
     (4) Infrastructure

12. You learned about the common causes for failure for each pillar of operational resilience. Match each pillar to its common causes for failure.

ANS: (1) Operations - Human errors, configuration errors, procedure errors, and common place accidents
     (2) Security - Malware, network attacks, unpatched applications, poor or limited authentification
     (3) Software - Resoure exhaustion, computational errors, inadequate monitoring, or failed upgrades
     (4) Infrastructure - Hardware failure, natural disasters, power outages, volumetric attacks

13. How does AWS help to mitigate each failures in each of the following areas? Match the correct answers.

ANS: (1) Operations - Automates continuous integration and delivery workflow, runs smaller code deployments
     (2) Security - Use AWS automation and tools, and provides AWS Identity and Access Management (IAM)
     (3) Software - Leverages automation, manages services end to end, monitors API access
     (4) Infrastructure - Enables customers to run applications and failovers across multiple AZs and Regions

14. Business agility means ________.

ANS: responding faster, experimenting more, and delivering results in the same or less amount of time.

15. Which of the following are Key Performance Indicators (KPIs) for measuring business agility?

ANS: All of the above

16. Being able to easily shut down failed initiatives without the pain and wasted resources associated with an inflexible on-premises environment describes which concept?

ANS: Fail fast

17. Identify the four key areas of cloud financial management discussed in this course. Select all that apply.

ANS: (1) establish cost transparency, to ensure visibility into and accountability for spend
     (2) cost optimization
     (3) planning and forecasting
     (4) cloud financial operations

18. Which of the following is not one of the four best practices of cost optimization discussed in this course?

ANS: Increasing security standards

19. Enabling cost transparency and leveraging tools for measuring and monitoring costs and usage data are examples of which key area of cloud financial management?

ANS: Measurement and accountability

20. Match each of the key areas of cloud financial management with its correct description.

ANS: (1) measurement and accountability - Establish cost transparency, to ensure visibility into and accountability for spend
     (2) cost optimization - Identifying waste, building cloud-friendly architectures, improve cost efficiency
     (3) planning and forecasting - Understanding current and future costs and IT needs, driving accurate planning
     (4) cloud financial operations -Identifying and investigating in people, processes, tools, and automation

21. Match each Amazon EC2 purchase options with its description.

ANS: (1) on-demand instances - Pay for compute capacity by the second with no long-term commitments
     (2) reserved instances - Make a 1 or 3-year commitment for a significant discount. Best for steady-state workloads
     (3) spot instances - Spare EC2 capacity; best for fault-tolerant, flexible, and stateless workloads