I am lucky enough in my current role to have a lab environment that is almost 1:1 with our production environment, so we use testinfra to test all our VM's in p

I am lucky enough in my current role to have a lab environment that is almost 1:1 with our production environment, so we use testinfra to test all our VM's in parallel, with tests tailored for each VM to the task it performs (database, application, load balancer, DNS, LDAP, SMTP etc). We can run tests on an entire environment in under 2 minutes. Far more holistic than the 20-30 minutes I described in that previous role, where the whole set of tests was run in a single vagrant VM, usually recycled to save time on spinning up a new VM for each run. There's a lot of great stuff you can learn from devops, but there also seems to be a large amount of cargo culting where people have cut & pasted certain solutions from a blog or something without understanding how to adapt it to their environment and make it work properly for them.