The high availability of IT services is critical to the survival of most modern businesses. IT Service Continuity Management or ITSCM as it is formally known, is the process of ensuring that IT facilities (such as computers, servers, network, applications) can be resumed within required and agreed timescales that the business defines. It's all about keeping the operation alive, proactively not reactively.
We use ITSCM to:- Create and maintain continuity plans
- Create and maintain recovery plans
- Perform regular BIA
- Assess the impact of changes to services
Business Impact Analysis (BIA) considers the disasters such as major events like the total loss of service. BIA is a really important activity that's used for every other process to kick off design requirements. For example, if you went and did a business impact analysis to figure out how to recover the business.
Examples of risks- Loss of systems
- Loss of data
- Unavailability of technical or support staff
Examples of threats- Power failure
- Flood
- Sickness/injury (personal)
We usually go out and work with different business units and come back with lots of great data. At the end of the day, we need to find out 'what they consider valuable'. You'll take that BIA and apply it towards monitoring, service level management, and then design for availability. It's a good idea to do a BIA as early as possible as one of the first tasks.
In Service Continuity, you build a continuity strategy. Essentially you build a plan to capture technology focus and include
recovery plans. For example - how to recovery exchange from failure? Recover active directory etc. Then we determine how they would be invoked or kicked off. In addition to that, we design a backup plan to recover from disaster or failure. We clarify how to perform backups, recovery and other types of technical items.
Examples of countermeasure- Off-site storage
- Work arounds
- Backups
- Redundancy
When do we use ITSCM?- New or changed services
- Occurrence of a major incident
- Changed SLR, SLA, OLA or contracts
Once a recovery plan has been developed, experience shows that testing ensures they are valid and work as intended. There are a variety of testing methodologies including; walk throughs, scenario tests, full tests.
See also- Single Point of Failure (SPOF)
- Fault Tree Analysis (FTA)