These terms are not interchangeable. Learn about the ins and outs of fault tolerance to highlight the differences between the two concepts.

Fernando Doglio

What caught my eye in this article: AIIMS, the Australasian InterService Incident Management System. It’s the equivalent of the Incident Management System (IMS) in the US.

Ian Jones

The system is highly configurable, allowing fine-grained A/B testing of failures at all levels of the microservice call tree.

Ephemeral port exhaustion can really ruin your day. Read this to learn how to deal with it, how to detect it before you have problems, and why you might run out of ports sooner than you expect.

Will Sewell — Pusher

This incident report from 2013 is a great read. It’s really two inches in one, including an analysis of why a remediation task from the first wasn’t completed in time to prevent the second.

David Poblador i Garcia — Spotify

There are a few nice tidbits in this interview, including this one:

[…] the health of the system no longer matters.  We’ve entered an era where what matters is the health of each individual event, or each individual user’s experience […]

Daniel Bryant – InfoQ

This article has introduction to implementing canary deployment and also includes a discussion of the potential downsides.

Erik [surname not given] — Rollout.io

Lots of great detail in this announcement, including an analysis of how (and why) they designed their load balancer to function entirely in userspace without a kernel bypass mechanism.

Nikita Shirokov and Ranjeeth Dasineni — Facebook

Metrics are great, right? Except sometimes they’re not, when the metric collection itself adds enough load to impair the system.

Jonathan Brown — Wallaroo

After adopting a “full ownership” philosophy, this company faced burnout, with five or more separate developers on call simultaneously. Read about their awesome solution involving a shared on-call rotation staffed entirely by volunteers, spurred by the incentive of extra compensation.

Brian Scanlan — Intercom

What exactly is SRE and how does it relate to DevOps? Earlier this year, we (Liz Fong-Jones and Seth Vargo) launched a video series to help answer some of these questions and reduce the friction between the communities. This blog post summarizes the themes and lessons of each video in the series to offer actionable steps toward better, more reliable systems.

Liz Fong-Jones and Seth Vargo — Google

After a load test uncovered a scaling issue, they dug deep, finding issues with garbage collection settings, cascading failures, and an overeager retry strategy.

Val Markovic — LinkedIn

These tips cover the basics and will be especially useful for teams onboarding engineers that have never been on-call before.

This article examines a case study of an EMS company attempting to adopt a just culture policy. There’s a great discussion of why it’s not a good idea to lay blame on individuals when systemic problems may be far more important.

Larry Boxman and Paul LeSage — JEMS (Journal of Emergency Medical Services)

In this third and final article in a series, Xero lays out their process for analyzing incidents after the fact. Thanks to the Xero folks for being so open about your processes and for taking the time to write these articles!

Karthik Nilakant — Xero

I like the nifty heat maps with example distributed traces. Neat idea!

JBD — Google

This latest in the CRE Life Lessons series takes on dependencies and how they impact a service’s SLO in obvious and subtle ways.

Robert van Gent — Google

This company discovered that the benefits of microservices came with some significant downsides. Here’s how they turned to chaos testing to improve reliability.

Meredith Courtemanche — TechTaret

Keeping in mind that this is written by the CTO of Gremlin, it contains some good points about buying versus building your chaos engineering system. It would apply to other chaos engineering services too — if there were any.

Matt Fornaciari — Gremlin, Inc.

Even as an experienced Terraform user, I learned about some Terraform features I hadn’t been aware of.

Nic Jackson — Hashicorp

In issue #98, I linked to a recording of John Allspaw’s DOES17 talk. In case you didn’t have time to listen, here’s a transcript. If you didn’t have time to read the Stella Report, I highly recommend reading this as an intro to the major concepts therein.

John Allspaw

“You can OOM a single NUMA node” thus entered my list of things to worry about when a box seems to have plenty of memory but still goes off and slaughters innocent (but big) processes.

Rachel Kroll

In this podcast episode, the panelists hold a retrospective for the snow-related delay of DevOps Days Baltimore. Toward the end they go into the idea of reliability and single points of failure with respect to conference planning. My favorite quote in the show, from Nell Shamrell-Harrington:

Incident Management is never about technology — it’s a people.

Nell Shamrell-Harrington and Nathen Harvey

I really love this Who, Me? section from The Register.

Simon Sharwood — The Register

This article has a great discussion of how to get started with chaos engineering — and how to avoid biting off more than you can chew.

Jennifer Riggins — The New Stack

Beamer is a stateless datacenter load balancer supporting both TCP and Multipath TCP (MPTCP). It manages to keep the load balancers stateless by taking advantage of connection state already held by servers.

Super-clever! The LB does keep state, but the size of the state is constant, unrelated to the number of connections flowing through it.

Adrian Colyer — summary, Olteanu et al. — original paper

Sometimes it’s worthwhile to lay everything out and describe just exactly what we’re up against as SREs. The analogies here are pretty awesome. Read this for a hefty dose of cynicism about the state of our increasingly computer-driven world.

Peter Welch