問47
頻出度★★★
サービス提供者が行う活動のうち, 稼働率の向上に有効なものはどれか。
平成28年度 秋期 ITパスポート試験 問47
マネジメント系サービスマネジメント › サービスマネジメントシステム
This question's explanation and your answers so far.
解説
問 47
Incorrectア
Measuring response time is an activity that gauges performance (response time) — how quickly a response is returned to a request. A fast response does not mean the system never stops, so it is not directly linked to improving the availability rate (the proportion of running time). This is a metric related to service performance management.
- イ
正解 The availability rate (availability) is the proportion of time during which the system is operating normally, and it is expressed as availability rate ＝ MTBF ÷ (MTBF ＋ MTTR). To raise the availability rate, the key is to shorten the downtime caused by failures. Choice イ, monitoring for the occurrence of failures, is an activity that detects failures as early as possible so that recovery work can start quickly, which leads to a shorter mean time to repair (MTTR). Since shorter downtime raises the availability rate, イ is the correct answer.
Incorrectウ
Managing the server configuration is a configuration-management activity that grasps and maintains which devices and software are configured in what way. Accurate configuration information serves as a foundation for operations, but by itself it is not a direct means of shortening downtime and raising the availability rate.
Incorrectエ
Recording the modification history of programs is an activity belonging to change management (version management), which records when, where, and why changes were made. It helps in tracking changes, but it has no direct effect on raising the availability rate itself.
ここがポイント
- Availability rate (availability) ＝ MTBF ÷ (MTBF ＋ MTTR). Shortening the downtime caused by failures raises the availability rate.
- Monitoring for failures leads to early detection of failures and quick recovery (a shorter MTTR), making it an activity directly effective at improving the availability rate.
用語