SRE Weekly Issue #183

Another issue of Increment, on a topic integral to SRE: testing.

It doesn’t matter if you’ve already read everything Charity Majors has written; in this article she’s still managed to find new and even more compelling ways to argue that we should embrace testing in production.

My two other favorite articles from this issue:

• What Broke the Bank (Chris Stokel-Walker)
• Tests from the Crypt (Tammy Butow)

Charity Majors — Honeycomb

That’s exactly what we hoped for.

They rewrote this critical service and carefully deployed it to avoid user impact, using a technique I love: run the new code alongside the old for awhile to verify that it returns the same result.

Jeremy Gayed, Said Ketchman, Oleksii Khliupin, Ronny Wang and Sergey Zheznyakovskiy — New York Times

This is aimed at Certification Authorities dealing with TLS certificate misissuance issues and the like, but it very much applies to any kind of incident.

BONUS CONTENT: An incident report from LetsEncrypt just a few days later included this gem, exactly in line with what Ryan wrote:

After initially confirming the report we reached out to multiple other CAs that we believed would also be affected.

Ryan Sleevi

Whose? Hosted Graphite’s. Definitely worth a read.

Fran Garcia — Hosted Graphite

Which brings me to this unpopular opinion: All code is technical debt.

However, debt itself isn’t bad. It can be risky, especially if misunderstood, but debt itself is not inherently good or bad. It’s a tool.

Dormain Drewitz — Pivotal

Blameless is running a free workshop on writing post-incident reports.

In this talk we will discuss the elements of an effective postmortem and the challenges faced while defining the process. We will introduce concrete methodologies that alleviate the cognitive overhead and emotional burden of doing postmortems.

Blameless