
SCADA 系统 are complex configurations of hardware and 软件, so thoughtful consideration of backup and planned restoration efforts should be performed before they may be needed.
Stephen Goldsworth, 系统工程 Group Manager at Tesco Controls, recently wrote an article for the November 2019 issue of 水 & 废物文摘》杂志. 文章的标题是 Safeguarding SCADA Systems, and describes concepts and approaches for establishing SCADA backup and recovery methods. Here’s a summary, click on the link above for the full text.
Supervisory control and data acquisition (SCADA) 系统 are integral for operating today’s water collection, 治疗, and distribution operations. They are built from complex arrangements of hardware, 软件, 网络, and communications technologies. Unplanned outages are possible for many reasons, so every facility needs to prepare by establishing and following a comprehensive disaster recovery (DR) plan.

Business Life Cycle Continuity
Creating a DR plan is one step in the never-ending business continuity life cycle. Without a DR plan, SCADA system recovery will be slow, disorganized, and expensive.

Identify Existing Conditions
The lifecycle approach to SCADA 系统 usually begins with the “identify” step, where documentation is identified, 更新, 或创建. More difficult is to assess the risks, which can include internal single points of failure like 网络 issues, or external issues like 权力 failure.
分析目标 & 成本
Once the SCADA system is documented and the risks are understood, it is possible to evaluate the cost of disruptions in conjunction with the cost of various safeguarding strategies.

Design Redundant Strategies
冗余在地理, 权力, 网络, and SCADA system levels is optimal, 但可能非常昂贵. The cloud can play a role by providing backup storage, as long as cybersecurity concerns are addressed.

Backups are also effective, but they must be rigorously maintained and require manual effort. The 3-2-1 rule for 软件 and data backups calls for users to:
- 创建 three copies (one primary and two backup)
- Store copies on at least two different media types (hard drive, tape, cloud, etc.)
- Keep one of those copies off site
创建 & 执行容灾计划
A comprehensive DR plan includes technical details, identifies all sources of information, and defines roles and responsibilities. It also describes how to operate certain processes in a manual mode during a DR event.
Measure by 培训, Testing, & 维护
The DR plan must be exercised, preferably under controlled conditions instead of during a crisis. 正如斯蒂芬所说:
Make sure staff are trained on the DR plan, and then prove out both the training and the plan itself by executing test scenarios and attempted recoveries. Good test plans will use actual backup media to confirm they are viable and will proactively exercise redundant components, 系统, and sites by triggering failovers from primary to backup elements. Redundancy 系统 and elements must be maintained just like any other mechanical or electrical equipment.
Close the cycle by continually updating the DR plan.
Seek DR Plan Expertise from a System Integrator
Developing a DR plan can be a daunting activity requiring a large and experienced team. End users should consider engaging a trusted system integration partner with a solid track record of developing DR plans while balancing technical and cost impacts.
的水 & Wastes Digest digital magazine version click here.
