In a previous blog post I discussed the complexity of securing Kubernetes environments, and some best practices. Unfortunately, even if we follow best practices in setting up and configuring our system, we can never eliminate all the vulnerabilities.
There are instances in life when isolation is actually welcome. One of those instances pertains to the I in the acronym ACID, which outlines the key properties necessary to maintain the integrity of transactions in a database. The time series database (TSDB) embedded in the Prometheus server has the C (consistency), the D (durability), and – somewhat debatable – the A (atomicity). But up until and including Prometheus v2.16, it did not have the I (isolation).
Last year, the Skylight team gave a talk called Inside Rails: The Lifecycle of a Request. In that talk, we covered everything that happens between typing a URL into your browser to a request reaching your Rails controller action. But that talk ended with a cliffhanger: Once we are in the controller action, how does Rails send our response back to the browser?
