Disaster Recovery or DR is a set of procedures that
companies follow to allow for the recovery of important technical
infrastructure and systems after a far reaching negative event. DR focuses on
technological systems that support critical functions of a company. A robust DR
plan enables a company to maintain or resume critical functions with minimal
downtime.
In this article, we're going to talk about your options for
disaster recovery in the cloud and then compare how AWS and Azure integrate DR
solutions into their services. But first, let us have a look at why DR is
important for your business.
What is Disaster Recovery and Why
Should You be Concerned?
Disaster recovery is a key subset of a company's business
continuity plan. The objective of a disaster recovery plan is ensuring that
under any circumstances, a company's vital and critical data is recoverable and
important applications can be brought back online. And this should happen in
the minimum amount of time possible.
According to the 2015 statistics for disaster recovery a one
hour downtime cost smaller companies an average of $8,000, medium size
organizations an average of $74,000 and large enterprises an average of
$700,000.
A number of
studies have demonstrated that a company could actually fail as a result of
loss of data. This is why planning for disaster recovery is of critical
importance.
Recovery Point Objective (RPO) and
Recovery Time Objective (RTO)
Two important measures for disaster recovery
as well as downtime are Recovery Point Objective (RPO) and Recovery Time
Objective (RTO).
RPO represents the age of files that a
business is required to recover, normally from backup storage, for the
resumption of normal operations post a disaster. The RPO determines the minimum
frequency at which the business needs to arrange for backups to be taken.
The RTO, on the other hand, is the amount of
time a business takes to recover these files from storage for the resumption of
normal operations after experiencing a disaster. The recovery time objective
can be translated to the highest downtime a business can bear before normal
operations resume.
For a business to be ready when disaster hits,
an all round approach is necessary. A robust disaster recovery plan includes
hardware and software, power and connectivity, networking equipment and regular
testing to ensure that disaster recovery is possible within the given targets
for recovery time objective and recovery point objective.
A Cloud Based Disaster Recovery
Plan
The implementation of a functioning solution
for disaster recovery requires, in most instances, a commitment in to invest in
physical data centers as well as hardware. However, given the rapid evolution
of Cloud based infrastructure, the upfront cost commitment to set up a disaster
recovery plan has reduced to a large extent.
The prime reason being that Cloud service
provides like AWS as well as Azure provide complete resource provisioning on
demand with custom and reasonable billing models.
The advantages of Cloud are not just
restricted to on demand technical infrastructure but also expand to assist in
the automation of the disaster recovery process with the help of their numerous
applications. A vast majority of these applications are service level
structures like Database and Storage Level Replication, Virtual Machine
Snapshots, etc. That said, maintaining a centralized utility for management as
well as migration for disaster recovery situations can help with
- On-premise
to Cloud transfers
- Across
different Cloud providers
- Across
different regions but with the same Cloud service providers
Most of the cloud infrastructures have set their
own standards for disaster recovery and data backup. The popular disaster
recovery solutions include Amazon's Disaster
Recovery Service and IBM's Disaster Recovery as a Service (DRaaS).
Third-party vendors such as NetApp provide extended DR capabilities on top
of the ones provided by the AWS/Azure.
In this article, we're going to compare the
two most popular cloud solutions - Azure Site Recovery and Amazon's Disaster
Recovery Services. We'll also see how well they fare against each other.
Disaster Recovery Plans on Azure
- Azure Site Recovery
Azure Site Recovery is categorized as Disaster
Recovery as a Service or a DRaaS solution. The implementation of DRaaS helps
provide continuity of business by allowing for the operation of business
applications and systems even if part of the system is down following an outage
or disaster.
ASR's
configurations can replicate workloads that were running on physical or
virtual machines via a Cloud provider like AWS or Azure either from a primary
location or secondary site. In the event that the primary site faces an outage,
Azure Site Recovery makes sure the secondary location is ready to take over.
Azure Site Recovery simplifies the
configuration task to quite an extent and can also simulate disaster recovery
situations that can be used for testing. It also centralizes the disaster
recovery management effort and aligns itself with the company's business
strategies ensuring the disaster recovery solution is functioning as needed.
When to Use ASR?
Azure Site Recovery proves to be a great tool
to replicate disaster recovery for multiple infrastructures in the event your
business has virtual machines functioning via a Cloud service provider.
However, instances where your businesses have inter region Cloud or inter Cloud
disaster recovery solutions, Azure Site Recovery may not prove to be the right
fit. This is because Azure's alternative Amazon Web Services support disaster
recovery natively for all almost all their services. Let's have a look at Amazon's
DR solutions.
Disaster Recovery Using Amazon Web Services
(AWS)
There are multiple benefits of utilizing AWS
to implement a robust disaster recovery plan. It requires minimal investment up
front and removes the need for expenses for physical resources needed to run an
onsite data center.
AWS provides businesses with the flexibility
to do away with the need to undergo a failover test of the complete site if
only a single application is malfunctioning. AWS is also easily and rapidly
scalable and allows businesses the option of a pay as you go model of billing.
This reduces the amount of up front expenditure needed for implementation.
Using Amazon Web Service, businesses have the
ability to completely automate their disaster recovery plan making testing,
documentation and maintenance much easier. The table below displays the AWS
equivalents to an on premise data center infrastructure.
Essential Amazon Web Services With
Efficient Disaster Recovery
Here are some of the Amazon services that have
a disaster recovery plan integrated into it:
- Regions & Availability Zones - The Cloud
infrastructure for AWS is segregated into regions and various availability
zones within a particular region. An availability zone consists of one or
multiple data centers with backup capabilities. These availability zones allow
for fault tolerant and highly scalable solutions as opposed to a single data
center.
- Amazon S3 - This provides a durable
infrastructure that can be used for storage and is designed primarily for
critical data storage.
- Amazon Glacier - Provides a substantially low
cost storage option for backup and data archiving.
- Amazon EBS- Provides the capability to put
together point-in-time illustration of data volumes.
- Amazon EC2 - Provides the ability to resize
the compute capacity in the Cloud. During disaster recovery, this allow for the
rapid creation of virtual machines that businesses can control
- Amazon RDS - Easy set up, operation and
scalability of a cloud based relational database
- AWS Cloud Formation - Provides system
administrators and developers an easy method to create an assembly of AWS
resources.
Summary
The quality of service offered by a business
depends on the reliability and availability of the service. Although companies realize their business
value, traditional DR solutions involve high cost and complexity. Cloud
infrastructures on the other hand have DR units integrated into their services
which cuts down the extra costs.
Cloud DR solutions evidently have an upper
hand over traditional systems because they are cheaper and more reliable. In
this post, we've made an in-depth comparison between the two popular cloud
service providers and how they approach Disaster Recovery. Let us know your thoughts
about how prepare your business for disaster recovery in the comments.
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About the Author
Limor is a technical
writer and editor at Agile SEO, a boutique
digital marketing agency focused on technology and SaaS markets. She has over
10 years' experience writing technical articles and documentation for various
audiences, including technical on-site content, software documentation, and dev
guides. She specializes in big data analytics, computer/network security,
middleware, software development and APIs.