The Recovery Time Objective (RTO) is a key point of the backup strategy design and configuration and it is essential to know how to calculate RTO to ensure the lowest downtime for your applications and services.
Companies asking for a zero RTO with minimum expenses it is a quite common situation, but to achieve such result are required big investments and a completely redundant environment. Not all businesses can afford such expenses and for a good design you need to find balance between affordability and reliable data protection.
Terms used in backup design
It is important to keep in mind the terms and the concepts used in backup strategies. When we talk about backup, we talk about RPO, RTO, Replicas, Disaster Recovery and so on.
Recovery Time Objective (RTO)
It refers to maximum amount of time that can be spent recovering systems after a crash or how long you can do without certain services or applications before you lose more money than you can afford. RTO depends on business needs and a disaster recovey plan must consider this factor.
Recovery Point Objective (RPO)
RTO is often used along with terms RPO (Recovery Point Objective) that is the acceptable amount of data that a company can afford to lose between the latest VM backup and the time of the VM crash (i.e. 4 hours) and MTD (Maximum Tolerable Downtime).
Work Recovery Time (WRT)
It's the time that your company can spend verifying the consistency of the data after recovery.
The backup design can be outlined as follow:
How to calculate RTO
RTO requirements are strictly related to the business. Some companies that operate 24/7 can have an RTO under an hour or aiming at zero, others can afford hours or days of downtime. If critical applications must be up and running within 15 minutes, RTO must meet the requirement.
First thing to define during the design of the backup strategy is the MTD at the application level, that is the total amount of time you can spend on recovery and health check.
To define the priority level of the applications for the business, you need to perform a Business Impact Analysis (BIA), a systematic process to determine and evaluate the potential effects of an interruption to critical business operations as a result of a disaster.
Business Impact Analysis (BIA)
You should consider the following steps during the BIA:
- Identify the business functions of various departments and their priority.
- Identify the possible losses incurred if each business function (individually) were interrupted.
- Establish how applications impact on business functions.
- During the restore process, ensure to have a plan B in place to mitigate the damage, that is, to increase the MTD.
- Set the MTD for business applications based on the potential losses.
To evaluate if the planned RTO can be achieved, three main points should be considered:
- Is your RTO requirement realistic?
- Do you have appropriate backup management?
- Is the recovery speed too low?
How to improve the RTO with Nakivo Backup & Replication
NAKIVO Backup & Replication offers a cost effective backup solution to protect VMware, Hyper-V, and AWS EC2 environments.
To improve and speed up the VM recovery process, Nakivo includes the following RTO-friendly features:
- Through the VM Flash Boot feature you can recover immediately an entire VM directly from a deduplicated and compressed VM backup stored in the repository.
- Using VM replication capability, you can create and maintain exact copies of your VMs (replicas) you can fire up in case of failure.
- Network Acceleration and LAN-free data transfer will speed up the recovery of even the largest databases.
- Creation of a VM backup appliance installing Nakivo directly on a network attached storage (QNAP, Synology, ASUSTOR, Western Digital are the supported NAS) making VM backup and recovery jobs faster and more reliable.
Using the capabilities included in Nakivo, the recovery times of your VMs can be dramatically improved. Additional info can be found at Nakivo website.
