Checking Your Backup Strategy with DBAChecks

Thu, Feb 22, 2018 3-minute read

Within the last 18 months I have become an accidental DBA and found myself grasping for information and tools in order to help manage the handful of database servers for which I am responsible. In that journey I discovered dbatools, which is a great community-built PowerShell module for configuring SQL Instances. If you’re not familiar with them, they have cmdlets that include the likes of Copy-DbaLogin, Find-DbaBackup, Get-DbaMemoryUsage, and Test-DbaPowerPlan. The last of these cmdlets I just listed really encapsulates the heart of the dbatools team as they are seeking to provide tools that reflect the best practices for data professionals. (If you don’t know that the Power Plan improperly set can cause performance issues, you should probably download dbatools and give it a shot).

Continuing this desire to help the community practice good things, the dbatools team has now released dbachecks This is a module which leverages pester (a powershell module for running unit testing) to run tests against your sql instances. You can find full details on what is required and how to install this module on their GitHub page here.

There are a large number of tests included with the dbachecks module, but you can create your own if you are familiar with writing tests in pester. A few of the built in tests that I found most helpful (and actually made me re-evaluate my production systems) were the tests for Backups.

After loading the module you can check out all of the predefined tests by running Get-DbcCheck. In order to get a list of all of the tests that check backups, use the -Pattern parameter to search for tests with matching keywords.

Get-DbcCheck -Pattern backup

In order to run the test you execute Invoke-DbcCheck with the following syntax to return successful passes of tests and failures.

Invoke-DbcCheck -Check BackupPathAccess,DefaultBackupCompression -SqlInstance localhost -ComputerName localhost

As you can see the backup location is accessible, and I have not configured compression for my backup sets. It also only took less than a half a second to run these checks. Now one of the most commonly unchecked aspects of databases backup is it will restore, and conveniently enough dbachecks has a test for that as well. Under the hood, this test is using the Test-DbaLastBackup to try restoring the database with the flag -VerifyOnly only:

Invoke-DbcCheck -Check TestLastBackupVerifyOnly -SqlInstnace localhost -ComputerName localhost"

The user databases for my SSRS instances were successfully tested, but there were no backups for my system databases. As a result I decided to double check and everything was in order, but you can never be sure.

So my suggestion is to set this as a scheduled task, or agent job and make sure that your backups are up to date. This module makes it so easy to make sure that you don’t lose your job because of data loss. This is just a highlight of a few of theses tests. Imagine the rest of the checks and tests that are possible with this module whether they are built in or they are one of your own creation. Download the module from the PowerShell Gallery and give it a try.