Introduction
If you've worked in software engineering for a while, you may have encountered the words RTO, RPO, or SOC 2.
I remember myself coming across these terms for the first time and being confused.
In this post, I want us to dive into all of them, especially RTO and RPO.
We won't dive too deep into SOC 2. I'll write a different post on that alone.
SOC 2
SOC 2 is a way to show that a company keeps data safe and secure. It stands for Service Organization Control 2. SOC 2 was created by the American Institute of CPAs.
It's based on five trust service principles: security, availability, processing integrity, confidentiality, and privacy.
Companies undergo SOC 2 audits to ensure they comply with these principles and demonstrate to their customers that they are managing their data responsibly.
RTO and RPO fall under the principle of "availability".
RTO
RTO stands for the longest time a system can be offline after a problem happens. It's the time within which a business needs to get its processes back up to avoid serious issues from the downtime.
For instance, if an important application has an RTO of 4 hours, it needs to be fixed and running again within 4 hours after it stops working. The RTO guides what steps and resources (like backup systems) are necessary to get everything working in the allowed time.
RPO
RPO stands for the maximum time we can afford to lose data. It tells us how recent the data needs to be when we restore it after a problem. RPO helps figure out how often we need to back up our data.
For example, if we have an RPO of 4 hours, it means we can't afford to lose more than 4 hours of data if something goes wrong. Losing data for more than 4 hours is unacceptable. To meet this RPO, we need to back up our data at least every 4 hours.
Relationship between RTO and RPO
RTO focuses on downtime and how quickly you need to recover, while RPO focuses on data loss and how much data you can afford to lose.
Generally, the lower the RTO and RPO, the more expensive a disaster recovery solution is, since a tighter RTO requires more advanced infrastructure and a tighter RPO requires more frequent backups
How to achieve RTO and RPO
Many modern cloud services have tools to help you achieve RTO and RPO, but some general ideas include:
Redundant infrastructure across multiple data centers.
Frequent data backups and replication to minimize data loss.
Automatic failover mechanisms to switch to backup systems.
Regularly testing disaster recovery plans to ensure they work.
Monitoring and alerting to quickly detect and respond to issues.