With extreme weather events happening more frequently and businesses moving more sensitive data to the cloud, creating data redundancies has become more important than ever. Data loss can now make or break a company, causing irreversible revenue losses or severe regulatory penalties.
Geo-redundant storage offers an appealing option to businesses that are more vulnerable to natural disasters, cyberattacks, and other outages that cause data loss. This article will explain what geo-redundant storage (GRS) is, how it can benefit organizations, common types, and how companies can evaluate different GRS options.
The Risks of Data Loss in Modern IT Infrastructure
Risks associated with data loss can be vastly different based on the nature of your business. For some organizations, data loss is a mere annoyance. For others, it can bring operations to a halt. It’s estimated that downtime costs businesses anywhere from $427 to $9,000 per minute on average. Data loss can greatly reduce revenue and productivity, and elongated outages can shake confidence in your business and lead to decreased trust.
What is Geo-Redundant Storage?
Geo-redundant storage is when data is stored in multiple geographically diverse locations. As a data replication strategy, this approach can improve data availability and reliability. At a minimum, data is stored in a primary region and is asynchronously replicated to a secondary location with geographically distinct features. This means that the same natural disasters or weather patterns are not likely to affect both regions. If there is a catastrophic failure in the primary region, systems can fail over to the secondary region and resume operability.
Why is Geographic Redundant Storage Crucial?
Geographic redundant storage is especially important for businesses that rely heavily on data availability. For organizations that can’t go long at all without access to their data, this form of redundancy offers an unmatched level of protection against data loss and a high level of business continuity.
How is it Different From Other Storage Methods?
The biggest distinguishing factor of GRS has to do with the location where data is saved. With local backups, data is saved in the same geographic area. Cloud storage can satisfy redundancy desires, but may not house data in geographically distinct data centers. Zone redundancy is similar to geographical redundancy, but protects data in zones within a region instead of in different regions.
Benefits of Geo-Redundant Storage
Because of how data is distributed with geo-redundant storage, this method offers greater data protection and durability, serves as a robust part of a disaster recovery plan, mitigates risk, improves business continuity, and boosts performance, while complying with regulatory standards for industries that demand high data availability and resiliency.
Data Protection and Data Durability
Because GRS replicates data to geographically distinct locations, it substantially reduces the risks associated with natural disasters, cyberattacks, and hardware failures. While one extra copy can improve data durability and protection, each additional region data is stored in will make it safer for organizations to manage critical information.
Disaster Recovery
According to the World Economic Forum’s 2024 Global Risks Report, extreme weather was listed as the second-biggest risk in terms of global impact for the next two years, as well as the biggest global risk for the next 10 years. Natural disasters are only increasing in frequency, which means businesses should plan for their inevitability. Having a geographically separated location for failover data allows organizations to rapidly switch to a secondary region, minimizing business disruptions and downtime.
Business Continuity and Risk Mitigation
Uninterrupted access to safeguarded data has a huge impact on business continuity. GRS can help organizations continue operations and maintain customer expectations without missing a beat. Data loss, unexpected disruptions, and system failures are significantly mitigated through GRS.
Performance
Performance is also a major consideration for GRS. Data availability doesn’t mean as much if latency increases and performance decreases in a failover location. GRS solutions should come with advanced techniques such as content delivery networks (CDNs) and intelligent routing to optimize network times and reduce latency.
Regulations and Compliance Standards
Not all industries need to use GRS, but some may be required to via regulatory guidelines. Sensitive data, such as personally identifiable health information and financial data, is subject to more stringent regulations. GRS can help organizations meet compliance requirements by nature of their data protection measures and improvements made to data availability. Having geo-redundant storage set up can also make audits and inspections run more smoothly with demonstrated data protection measures in place.
How Does Geo-Redundant Storage Protect My Data?
Here’s a breakdown of how geo-redundant storage works to protect your data:
- Data is stored in a primary location and then replicated to a secondary region, generally hundreds of miles away from the original site.
- Asynchronous replication means that data may not be an exact copy on the backup site, but it can still significantly minimize data loss.
- A catastrophic failure in the primary region, such as a natural disaster or data breach, can trigger a failover to the secondary location. Data can continually be accessed from this location, and the switch happens with little downtime.
- Having multiple copies of data improves durability and protects data from a wide range of threats. Once the threat has passed in the primary location, data replication from the secondary to the primary region can start the failback process
Types of Geo-Redundant Storage in Azure
There are a few main types of geo-redundant storage you can find with different cloud providers. Here are some examples of types of GRS in Azure, but there are similar structures that can be found with other cloud providers, such as Google Cloud Platform and Amazon Web Services.
Locally-Redundant Storage (LRS)
With LRS, data is copied synchronously three times in the primary region, all within one location. LRS is the most cost-effective redundancy option available in Azure but provides the least durability since it only replicates data within one data center. This makes it suitable for scenarios where low-cost storage is needed and the data doesn’t need to be replicated across multiple regions. Applications that need high durability and availability should not choose this option.
Zone-Redundant Storage (ZRS)
With ZRS, data is copied synchronously across three Azure availability zones, with all zones residing in one region. This could be used with replication to a secondary region for high-availability needs. This makes it a good choice for applications requiring high availability within a region, such as mission-critical workloads where regional redundancy is essential but where cross-region replication is not necessary.
Geo-Redundant Storage (GRS)
Azure defines GRS as synchronous copying of your data three times in one primary location with LRS, along with asynchronous copying of data to one physical location in a secondary region. In that second region, data is also copied synchronously via LRS three times.
GRS offers durability for storage resources of at least 99.99999999999999% (16 9s) over a given year.
Geo-Zone Redundant Storage (GZRS)
GZRS uses ZRS to copy data synchronously in three Azure availability zones in the primary region. In the secondary region, data is copied synchronously three times using LRS.
With a GZRS storage account, you can continue to read and write data if an availability zone becomes unavailable or is unrecoverable. Additionally, your data also remains durable during a complete regional outage or a disaster in which the primary region isn’t recoverable.
Read-Access Geo-Redundant Storage (RA-GRS)
GRS and GZRS can also have read-access configurations, meaning that users could access data from either location which allows for better performance and access, even if it’s the secondary region.
If your storage account is configured for read access to the secondary region, then you can design your applications to seamlessly shift to reading data from the secondary region if the primary region becomes unavailable for any reason.
How to Evaluate Your Geo-Redundant Storage Options
Not all businesses require the same level of redundancy, and while it may feel obvious to choose the redundancy option that provides the most coverage and failback options, this can often be overkill or unfriendly to budgets. Consider the following factors when weighing geo-redundant storage options.
Durability and Availability
Read through a cloud provider’s documents or ask questions about the following:
- How often is data replicated to the secondary region?
- What does the provider’s track record look like when it comes to preventing data loss?
- Can the provider meet requirements for recovery time objectives (RTO) and recovery point objectives (RPO)?
Latency and Performance
If data can be read from a second region, what impact does that have on performance? Does the improvement make the functionality worth the cost? If you are evaluating two locations, what does the network connectivity look like between them? How can you ensure data is being transferred optimally between sites and not negatively impacting write performance?
Failover and Recovery
Understand how long it takes for data to failover to a secondary location and what it would take to recover critical business systems after a primary site failure. What does the recovery process look like, and what’s required of the business in the event of an emergency?
Even after you choose a storage option, don’t just rely on failover systems to work – test them regularly to ensure they will operate successfully when it matters.
Security
Ensure that the storage provider has the following controls in place:
- Encryption: Data should be encrypted at rest and in transit
- Access controls: Systems should be in place to prevent unauthorized access that may compromise failover protocols
Cost Considerations
When weighing necessary features, the final deciding factor can come down to cost. There are costs associated with transferring data between regions, adding redundancies, and pricing per gigabyte. Separate the mandatory features from optional ones that would be nice to have, and plan a storage approach that works for your business goals, regulatory requirements, and budget.
Selecting the Right Geo-Redundant Storage Solution
The right GRS solution is going to be completely unique to your business. It will depend on where your team operates, the sensitivity of your data, and how prone your geographic area is to natural disasters, among other things. Working with a partner to ensure you’ve chosen the geo-redundant storage solution that is right for you can mean you save your data from disasters or outages and keep systems running as normal. If you have questions about choosing between geo-redundant solutions, TierPoint can help with IT advisory consulting. Contact us to learn more about our services or read more about our storage as a service solution.
