From an IT perspective, disaster may arrive in the form of fire, flood, theft, vandalism, computer failure, building collapse etc.
Nobody plans to have a disaster, but you can plan to mitigate the effects of a disaster. We look at the whole company IT installation and how the business would be affected if that installation were seriously degraded.
One obvious area is the need to carry out reliable data backups, so that data can be restored, after a data loss.
Disaster recovery is so much more than good backups
Just think about these:
Replacement server - how long to get & restore data & programs
Workstation PCs - replacement time / was the data backed up / installed programs
Building power - Where can I get standby power from TODAY!
Remote Workers - They need to be connected to your server
Internet connection down - Temporary Internet facility
Then there are new premises (temporary or permanent), replacement of stock, additional staff, compliance failures, insurance claims, failure to meet contracted orders and on and on and on.
There is little point in waiting for the disaster to strike, and then realise that the plan was not good enough. So we test the plan and adjust it if necessary.