RTO vs. RPO – What is the Difference?
As long as your production systems and essential functions are working fine, it’s a success for your department. But, at a given point in time, an unacceptable disruption to your operations occurs, it poses a significant threat. Often, with little or no warning, disasters do occur unexpectedly. This urges you to conduct risk calculations and establish recovery priorities, an essential element of both the Business Continuity and Disaster Recovery (DR) planning process.
In the event of a major disruption, your system needs to be recovered, and you cannot ignore it. Two critical decisions that reflect your company data loss tolerance during a potential disruption are Recovery Time Objective (RTO) and Recovery Point Objective (RPO). The RPO vs. RTO objectives has to be set in line with business continuity. These parameters are essential business metrics that play a key role in determining the frequency of scheduling backup runs.
While RPO and RTO meanings are related, these two components of the company’s Disaster Recovery Plan and Business Continuity Strategy differ in their core objectives, purpose, data priority, and usage. During a disaster event, every minute of downtime can spell thousands in lost revenue and slowly diminish customer confidence in your business. Henceforth, to build a solid disaster recovery RTO vs. RPO strategy, it's crucial to understand what is RTO, RPO, and their differences. With RTO & RPO values, you can develop a solid disaster recovery and business continuity plan that outlines the risks, recovery needs, and backup solutions that your enterprise should put together in place.
The target time taken by the organization to recover its applications and processes after a disaster occurs is known as the Recovery Time Objective (RTO). The recovery timeline is a crucial parameter to determine the downtime tolerance level of a business. The RTO answers the question, “how long can an application be down to get up and running again after a disaster without incurring significant business loss and customer anger”. This key metric can help you calculate the duration of time between recovery and acceptable data loss.
However, the RTO objective is not about just determining the duration between the onset of the disaster and recovery. It also accounts for defining the recovery steps that the IT teams should undertake to restore its applications and data. If IT has invested in failover services to recover high-priority applications, you can achieve RTO in mere seconds.
To calculate RTO based on the priority of business applications, it’s vital to make your RTO as accurate as possible.
- RTO near zero: Require failover services for mission-critical applications
- RTO of 4 hours: On-premise recovery from bare-metal restore ending with full application and data availability
- RTO of 8+ hours: For non-essential applications that can be down for days without causing any serious damage to the business
Examples of how to use RTO:
- If the minimum possible restore time is 2 hours, an RTO of an hour can’t be met.
- In another case, if you have set an RTO of 4 hours and there’s a system failure at 12 PM, then the server would be repaired and up and running by 4 PM which means the target RTO is met.
- If your RTO is set at 2 weeks, the investment would be much lower as you have enough time to recover data after the disruption has occurred.
To put it simply, Recovery Point Objective (RPO) is the amount of data the business can afford to lose and continue to function without causing any significant damage to the business. RPO ensures business continuity with the acceptable duration of data loss tolerance during downtime. Defining the amount of time “acceptable” by your company is extremely crucial in your business continuity plan. The longer the RPO, the more potential for data loss due to extended downtime. RPO seeks to answer the question, “ How much data can the business afford to lose?” In other words, RPO determines the age of data that you must recover to resume business operations to normal.
RPO sets the stage for determining your disaster recovery (DR) plan. Therefore, it’s significant to assess the criticality of data to decide which applications, processes, or information need to be recovered. Based on the level of criticality, you should restore the data. Since RPO is listed in the specified timeframe of the last backup and the type of backup, RPO entirely depends on your backup system. Data backups with individual RPO can be typically automated every hour, 24 hours, 12, to 8 to 4 hours, or maybe every 10 minutes. This means for 1-hour RPO, you can lose one hour’s worth of data, or if you are okay to lose 24 hours-worth of data, so your RPO is set to 20 hours.
While maintaining a near-zero RPO is possible through failover/failback strategies, but that’s an expensive undertaking. Based on the priority of your mission-critical applications, you can schedule the RPO balancing your budget:
- RPO of near-zero: Use continuous data protection (CDP) or replication (mission-critical data)
- RPO of 4 hours: Use near-continuous data protection (CDP) that uses scheduled snapshot replication
- RPO of 8-24 hours: Use existing backup solution (data that can potentially be backed up from other repositories)
Examples of how to use RPO:
- If there’s a system outage at 2 PM, and the system automatically performs a backup at 11 AM, the information is saved in a usable format in the most recent backup. The RPO should be 11 AM which means the business can lose 2 hours worth of data without disrupting business continuity.
- Again, if your RPO is 6 hours, you must perform a backup every 6 hours considering that every 24 hours might pose a risk of data loss. But if you schedule backup every 1 hour, it might cost you much.
Essential Points of Differences Between RTO and RPO
Realistically, a solid understanding of recovery time objective vs. recovery point objective can narrow the knowledge gap and help you set your objectives by budget, resources, and of course, application priority. Take a look.
- RTO is measured from the starting of an outage, whereas you can measure RPO after a service disruption.
- RTO determines the time in the future to recover applications and processes to be backed up and running. RPO deals with the time in the past before the data loss when data was preserved to the last recent backup, which the company can recover data to resume normal operations.
- RTO has nothing to do with the data loss and mostly deals with the target time for IT system restoration after a disaster. Whereas, RPO is the acceptable amount of business downtime causing data loss from the time of disruption to your last backup.
- RTO includes the steps taken by the IT to mitigate or recover from different disasters. But, RPO determines how far back the IT team must go till the last point in time and what must be done to return operations to a pre-disaster state.
- RTO has diverse restoration times that rely on several factors such as linear time frames, day of the event, etc. which further complicates its calculation. RPO is easier to calculate and implement as the data usage is largely consistent and includes fewer variables.
- Since RTO includes recovering the entire infrastructure, the recovery cost dramatically rises in meeting the near-zero RTO requirement. However, granular near-zero RPO replication simplifies the cost and effectiveness of recovery as siloed information can be recovered faster. Moreover, longer RPO is affordable, unlike restoring the entire infrastructure.
Achieving RTO and RPO: The Zmanda Difference
Keeping the operations highly available and accessible 24/7/365 is every business dream. But calculating RTO and RPO requirements might involve considerable risks of data loss and the costs of mitigation. Besides, during a longer period of downtime, if RTO and RPO objectives are not realistic, this might hit your business really hard. The result? Lost reputation, customer trust, and hundreds of lost transactions! Therefore, choosing the right recovery partner is critical to meet your recovery objectives. This is where you need to evaluate the cost-benefit equation by improving the RTO and RPO metrics as a part of your disaster recovery plan.
Leave it all with Zmanda’s comprehensive all-in-one cloud-native disaster recovery solution, which unifies backup, disaster recovery, and secure gateway access support solutions to scale backups across geographies and any number of workloads. Zmanda’s native code architecture can help you with instant recovery of mission-critical applications and data, and multiple types of backup stores while keeping your recovery times to a minimum. Besides, the Amazon glacier storage architecture also offers a faster storage architecture that facilitates a seamless hybrid backup. In addition, with multi-layered security, Zmanda customers can expect enhanced security during recovery and backup that reduces data management costs without impacting their businesses.