Recovery Point Objective (RPO) generally refers to estimating how much data loss an enterprise can experience within a period most relevant to its business before significant damage occurs, from the point of a disruptive event to the latest data backup.
The RPO helps determine the amount of data a company can tolerate losing during an unforeseen event.
What is RTO?
Recovery time objective (RTO) often refers to the amount of time an application, system, and process can be down without causing significant business damage and the time spent restoring the application and your data to resume normal business operations after a significant incident.
Calculating the recovery time objective (RTO) for your business is critical to your disaster recovery plan.
What is the difference between the RPO and RTO?
Although both recovery goals are similar in measurement metrics, their approach differs based on application and data priority:
The recovery point objective (RPO) addresses the maximum amount of data loss, helping to inform the development of a backup strategy. The recovery time objective (RTO) addresses recovery time and helps inform the development of a disaster recovery strategy.
Where RTOs focus on application and system restoration to allow normal resumption of operations, RPOs are only concerned with the amount of data loss after a failure event. However, the RPO takes into account not only lost data; calculates the risk and impact on overall customer transactions rather than the downtime of business operations.
Costs also fluctuate between the two objectives. The costs associated with maintaining a demanding RTO can be higher than a granular RPO because the RTO calculates the time frame to recover your entire business infrastructure, not just the data.
Because RPOs require you to perform scheduled backups at the correct intervals, data backups can be easily automated and implemented. However, this is virtually impossible for RTOs as they involve all IT operations in the recovery process.
Based on the fewer number of variables, RPOs may be easier to calculate due to the consistency of data usage. To calculate the RTO, companies will typically go through a slightly more complicated process, as restoration times depend on several factors, including analog time frames and the day the event occurs.
A shorter RPO means losing fewer data, but it requires more backups, more storage capacity, and more computing and network resources for the backup to run. A longer RPO is more affordable, but it means losing more data.
The calculation variables may also differ depending on the classification of the data. A good practice for any business is to differentiate data at critical and non-critical levels by defaulting their RPO and RTO in order of priority.
Examples of RPO and RTO:
To explain the difference between RTO and RPO, let’s take the example of a bank, but in two different scenarios:
At 9 am, an application has been affected on the bank’s main server, stopping services locally and online for 5 minutes. The bank’s RPO counted data loss as 15 minutes and its RTO counted recovery time as 10 minutes to restore systems and applications. Therefore, the bank was within the parameters of both objectives.
At 3 in the morning, the same bank faced a systems shutdown for an hour. Since the RPO only counted 15 minutes of data loss and the recovery time objective only counted 10 minutes of downtime, this meant that 50 minutes of downtime was not counted.
However, due to the timing of the shutdown, the data loss was not exponential, as the recovery process occurred during a period of low traffic for the bank.
How to reduce RPO and RTO?
Mapping your recovery goals should be done simultaneously, taking into account time, money, and company reputation. Collaborative input from all departments should help form a reliable business impact analysis. The information must consider how they operate, the data they handle, and the impact on all users to predetermine the order of priority of their most critical RPO and RTO.
From this information alone, you can compare the costs of downtime to the impact on the business, looking at the variables of lost revenue, wages, stock prices, and recovery expense, and then forecasting the worst incident that could face your business. In this way, senior management can proceed with business continuity planning and implement sensible data protection and data recovery protocols.
Long-term RPO and RTO optimization:
As the company grows, the values of the two key parameters will undoubtedly change. Therefore, the constant evaluation, testing, and measurement of your RTOs and RPOs will help to obtain proper disaster recovery planning to prepare for any shortcomings that may arise unexpectedly. The three main areas to help reduce the overall impact on the organization (and your wallet) include (but are not limited to):
More backups give you more data to access should a situation arise, reducing both data loss and the amount of time it takes to restore it.
Save time and money by isolating key blocks of mission-critical data that have changed since your last backup. This will allow data backups comprising only information that has changed within the given period.
By replicating your data, you instantly have a copy of your data that you can fall back on in the event of a disaster, lowering your recovery time objectives. Your RPO will be determined by how often you replicate your data. As a general rule, replication at a higher frequency means a lower RPO.
RPO and RTO test:
As with any business element, from marketing to processes, hardware, and software, RPOs and RTOs are not a replacement for testing and measurement. Here are three ways to keep and evolve your goals in line with potential business risks and threats to ensure business continuity.
Periodic checks of data backups:
Regularly assess your key backup parameters, looking at retention plans, granular backup restore points, automation, and protection variables, increasing the number of snapshots you have of critical data. The goal is to account for all measures to protect your data in the event of a disaster.
Review and improve:
Periodically review your disaster recovery plan, evaluating key employee roles, backup processes, and hardware modifications. This will be influenced by your most recent RTO and RPO. Both go hand in hand, so keep all items updated at regular intervals of the year.
Do not dispose of the 3-2-1 rule in the Trash folder:
Keeping at least three copies of data in two separate storage locations with one copy of data stored offsite can save your data if one of the storage locations becomes inaccessible or affected due to human error, natural disasters, or a cyber attack.
How might the RTO and RPO develop over time?
To determine how much a disaster may cost your entire operation, consider the cost of system downtime. The impact on employee productivity lost billable hours, lost sales from online activity, regulatory compliance obligations, the impact of virtual environments, etc.
Another aspect that can influence the priority and even the configuration of your RPO and RTO is the development of the company internally and externally.
Influential changes, such as additional service provisions, structural and personnel changes, data growth, location, etc., can change objectives completely. Here, regular testing and review are an absolute must for successful disaster recovery.
RPO and RTO to recover from any disaster:
Your RPO and RTO weigh the most critical variables in the worst-case scenario and provide a hedge against potential devastation to your business. Keep them current and in line with all critical business metrics, allowing your IT department to determine application priority and estimate the maximum length of potential downtime.
These, in turn, will enable a reliable risk assessment foundation for implementing the appropriate failover services and thus ensuring the high availability of any business-critical application, even in the face of a disaster.