The building you cannot enter
A flood closes the street where a firm's office stands. Nobody can go in for three weeks. The servers that hold its sales data are inside. The firm has a backup, but nowhere to restore it.
A firm that plans ahead has a second place ready to work from. How ready it is decides how fast the firm is back.
Key words
| Word | What it means |
|---|---|
| Recovery site | a second place to run systems if the main one is lost |
| Hot site | a site with equipment running and data copied across at once |
| Warm site | a site with equipment ready but without the latest data |
| Cold site | an empty space with power and a link, but no equipment |
| Disaster recovery | getting systems working again after a big failure |
| Business continuity | keeping the vital parts of a business running through a crisis |
| Failover | switching to a spare system when the main one fails |
| Backup | a spare copy of data |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can describe hot, warm and cold sites and choose one for a firm.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Three levels of ready
A hot site is a copy of the main site that is already running. Data is copied across all the time. Failover takes minutes. It is the quickest and the most costly.
A warm site has equipment in place but not the latest data. You restore the latest backup first. It takes hours to a day or two.
A cold site is an empty space with power and an internet link. You bring in equipment and restore everything. It takes days or weeks. It is the cheapest.
Hot, warm and cold sites compared
| Feature | Hot site | Warm site | Cold site |
|---|---|---|---|
| Equipment | Installed and running | Installed, not running live | None, so you bring it |
| Data | Copied across all the time | Last backup is restored | Restored from backup after set-up |
| Time to be back | Minutes to hours | Hours to a few days | Days to weeks |
| Cost | Highest | Middle | Lowest |
| Suits | A bank or a live sales system | A firm that can wait a day | A firm that can wait weeks |
The cells students fill in are left blank in this preview.
Check
Have a go
Check
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.