It’s no surprise that most businesses that are running SQL Server haven’t exactly been falling all over themselves to jump into the cloud. There are a lot of good reasons not to rush into cloud implementation. SQL Server supports most businesses' mission-critical applications, and moving them anywhere involves a high degree of risk. The typical payback for the cloud is reduced ROI resulting in an unfavorable risk-versus-reward ratio.
Businesses have already made the investments to run their mission-critical databases and the databases are working. Saving just a little money isn’t worth the possible downtime or other potential service interruptions. Plus, many organizations are leery of the cloud for databases because of data ownership issues. Also, in the cloud, data no longer resides within the direct control of the organization.
Low-Impact Cloud Options
While all of these things are true, there are ways that you can incorporate the cloud into your operations without taking the giant step of moving your mission-critical databases into the cloud. Incorporating the cloud for backup and disaster recovery are two low-impact options that can allow you to take advantage of the cloud without the risk of moving your mission-critical on-premise databases. One of the best ways to do this is to take advantage of one of the Infrastructure-as-a-Service (IaaS) offerings from a cloud vendor such as Amazon or Microsoft. Using IaaS, you can deploy one or more virtual machines (VMs) in the cloud and then use those VMs just as if they were part of your own infrastructure. This is quite different from the Platform-as-a-Service (PaaS) and Software-as-a-Service (SaaS) offerings that you might be more familiar with.
Microsoft’s first push into the cloud with Windows Azure and Windows Azure SQL Database (formerly known as SQL Azure) focused on PaaS, leaving a lot of customers with the impression that the cloud had to be an alternative to their existing on-premises database installations. Microsoft initially resisted acting as an IaaS provider. However, the success of Amazon’s EC2 has pushed Microsoft and Windows Azure squarely into the IaaS. Using a vendor’s IaaS solution allows you to essentially deploy your own VMs on the cloud vendor’s public infrastructure. These VM’s are a lot like running a SQL Server instance in a remote data center. You deploy a copy of Windows Server and install a SQL Server instance on the VM SQL Server is running on a—a VM that’s hosted on the vendor’s infrastructure. Network virtualization can bridge you on-premises network to the cloud infrastructure.
Take Advantage of AlwaysOn Availability Groups
What are some of the SQL Server features that you might be able to take advantage of with IaaS? One of the most immediate uses could be SQL Server’s AlwaysOn Availability Groups. AlwaysOn Availability groups was first introduced with SQL Server 2012; this feature allows you to provide a high availability solution for your SQL Server instances for failover and disaster recovery. SQL Server AlwaysOn Availability Groups can protect multiple databases by replicating all of the database transactions to up to four replica servers. Combining IaaS with AlwaysOn Availability Groups enables you to create and host your replicas in the cloud, creating a high availability solution without the need to setup a your own high availability/disaster recovery site. If your primary site or your primary SQL Server database fails, then the database instance in the cloud can provide data until the primary on-premise database is established. You can gain these high availability benefits without the need to spend any additional capital. With the cloud, you only pay for the resource that you require.
Other SQL Server technologies that can be easily incorporated into the IaaS cloud scenario include database mirroring and log shipping. Like the AlwaysOn Availability Groups solution, you can set up database mirroring or log shipping where your production SQL Server instance is running on your on-premises servers—and the VMs running in your IaaS cloud act as the backup.
Hyper-V Replica Option
If you’re SQL Server instances are running in Windows Server 2012 Hyper-V, another ready-to-go option for cloud-based data protection might be Hyper-V Replica. Unlike the SQL Server-specific solution that can provide transactional consistency, Hyper-V Replica can have some minimal data loss but still provide a very cost-effective disaster recovery option that can be cloud-enabled.
The cloud doesn’t have to be an all-or-nothing solution. Implementing cloud technology doesn’t have to be threatening, and you don’t need to move your mission-critical databases and applications into the cloud in order to gain some important cloud benefits. Data safety is job number one for the DBA, and IaaS offerings can allow you to incorporate the cloud in a low-risk fashion to provide enhanced data availability.