I saw a question recently from an individual that was trying to decide if it made sense to move their databases to the cloud. In this case, management wanted to move, but the technical staff had concerns about Disaster Recovery in the cloud. These are very valid concerns for any system, as technical staff is often responsible for data, regardless of who decides on the architecture of a system.
The concerns got me thinking a bit. Is the cloud safer for DR? It’s certainly an “it depends” question, especially as the “cloud” isn’t necessarily the same thing for each of us. Some of us would use IaaS, with VMs in the cloud. Others might choose PaaS, with RDS or Azure SQL Database as a platform. Still others might want something like Managed SQL Instances, which is like IaaS+, or maybe PaaS#. I’m not completely sure how to classify this.
In any case, your choice of cloud architecture can mean better or worse DR. The closer you are to IaaS, the more that you still have the same responsibilities that you might have inside your own data center. The difference is that hardware replacements or options are often quicker to procure, though perhaps with limited choice.
If you choose PaaS, then you have different DR capabilities and responsibilities. Your vendor might handle some aspects of DR and remove the need for you to worry about hardware, or regular backups, but you might need to worry about other items. Your vendor might give you PIT recovery, but you might not want a database replacement in a busy system, especially if you’ve processed a few thousand transactions since someone ran that UPDATE without a WHERE batch. In that case, perhaps you want to ensure you can restore your database elsewhere, or you have other options.
Many of us know that managing systems is complex work. Not every environment can be handled in the same way, and we often implement exceptions in both technology and staff knowledge. Ensuring your application and environment can recovery from a DR situation often requires detailed knowledge of both requirements and capabilities of the environment. While I’m not afraid of migrating to the cloud, I’d want to be sure I was prepared to answer questions from management if there are issues. After all, they’re going to look to me, not some vendor, for answers.
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