Calculating Availability

Write up an SLA for your platform that breaks down acceptable amounts of downtime for your application and for third party services separately. Also define periods of excused downtime and caveats for reduced functionality of non-critical components.

ABC Company Hosted Applications

ABC Company shall provide general platform uptime of 99.9%. This shall exclude a regular maintenance window from 1am - 5am CST every Sunday, as well as windows from 1am - 5am on other days provided that ABC provides 24 hours of notice.

ABC Company Critical Third-Party Components

Some components of our system are beyond our control, and thus, we can only pass through the provided SLA of these vendors. We only work with vendors who provide an SLA of 99.9% or better for all critical services.

ABC Company Non-Critical Components

Those components deemed non-critical (listed below) are subject to a 95% uptime SLA. These components are not core to our offering, but provide certain "nice to have" functionality. In cases where these services are not available, our platform shall continue to operate and provide core functionality as normal.