SRE / DevOps / Kubernetes Weekly Collection#29(Week 34)

• In this blog post series, I collect the following 3 Weekly Mailing List I subscribe to, leave some comments as an aide-memoire and useful links.
• Actually, I have already published the same content in my Japanese blog and am catching-up in English in this series.
• I hope it contributes to the people browsing this kind of information as a reference.

DEVOPS WEEKLY ISSUE #503 August 16th, 2020
SRE Weekly Issue #231 ←On vacation.
KubeWeekly #230 ←On vacation.

DEVOPS WEEKLY ISSUE #503 August 16th, 2020

News

eBPF aims to make the Linux kernel programmable, without the need to load kernel modules or compile custom kernels. This new site is a great introduction and links to several interesting projects utilising eBPF.

• An io page of eBPF.
• From the eBPF intro, there are tutorials, blogs, videos, and various explanations that are wonderful. It’s time to try this one.

A post both on OSPF datacenter-scale networking, and on the risks of silos when choosing technology.

• The title is “What I’ve learned about scaling OSPF in Datacenters”.
• The highlighted part is interesting. Although I am not as good as the writer, I mainly work in the Network realm, so I read it interestingly.
  ○ “One of the things I’ve learned recently is that OSPF shouldn’t be used for Clos leaf-spine networks because of scale.”
• I can feel it well. When talking about the network design, it is inevitable that we will discuss it while writing the image that each person has in their head on the whiteboard or alternatives.
  ○ “I think whiteboards are the most important tool for network design currently available, which makes me sad.”
• The four issues of OSPF are as follows.

1. the effect of flooding
2. the size of the link state database
3. the speed of SPF calculations
4. the ability for OSPF to carry a large number of prefixes.

Cortex and Thanos are two projects which help scale Prometheus. This post covers some of the background and collaboration between the projects.

• The title is “How the cortex and Thanos projects collaborate to make scaling Prometheus better for all”.
• A story about CNCF’s Sandbox project that scales Prometheus, “Cortex “ and “ Thanos “, learning from each other and evolving while influencing each other. Although reaching a consensus takes a long time, and they have to convince a wider group of people., I feel that the fact that they are contributing to each other and that they are able to consolidate their knowledge into a form is incredible.
• At PromCon 2019 , Tom Wilkie and (co-creator of Cortex) Bartek Plotka (co-creator of Thanos) talked about their similarities and differences. As a follow-up, there’s a video embedded in PromCon Online that talks about how the collaboration has grown stronger over the past year.

The differences in approach between the major clouds are interesting to consider, especially if you’re most familiar with one of them. This post looks at various network routing and load balancing options.

• The title is “Cloud Traffic”.
• An article that the author has been steeped in AWS technology for five and a half years , was shocked by watching a video of “Traffic Director “, titled “ Build an enterprise-grade service mesh with Traffic Director “, and shared related information and his thoughts.

I’ve always liked OpenResty, which is an Nginx variant with built-in support for Lua scripting. This post is a nice introduction and a good example of dynamic configuration.

• The title is “Retrying dynamically configured upstreams with OpenResty”.
• An introduction article of “OpenResty” which is a web platform that compiled nginx with LuaJIT.

Nearly everyone will have used SQL for some database work at some point. This post takes a critical look at the language and points out some issues, and proposes some improvements.

• The title is “We Can Do Better Than SQL”.
• An article that answers the following two questions. It explains the history of relational models and how SQL was created.
  ○ “Why create a new query language?”
  ○ “What’s wrong with SQL?”.

Another post on a query language. PromQL, from Prometheus, is increasingly used in other tools. In the absence of a proper specification, some efforts are underway to provide a correctness testing tool.

• The title is “Comparing PromQL Correctness Across Vendors”.
• As one of the efforts taken because there is no proper specification in PromQL , an article that explains the comparison using PromQL Compliance Tester, a tool that compares Prometheus and PromQL API implementation of each vendor .
  ○ “TL;DR: See the details of all PromQL compliance test results on our PromQL Compliance Test Results page”
• Two goals in mind:

1. Creating transparency for users (enabling them to make better choices)
2. Making it easier for projects or vendors to spot and fix bugs in their PromQL implementations.

I like finding relevant research topics for this newsletter, for the points made in this article about the relevance of research to IT practitioners. Some good pointers to recent security, privacy and cloud research topics.

• The title is “Security, privacy, and cloud: 3 examples of why research matters to IT”.
• It introduces three positive topics covered in the latest Red Hat Research Quarterly and ties them to the challenges IT professionals are currently facing.

1. Security usability
2. Data sharing and privacy preservation
3. Open source cloud operations

Tools

Fregot is a powerful repl for working with Rego, the Open Policy Agent policy language. It provides useful error messages and testing tools for iterating on policies.

• The GitHub page of the OSS tool “Fregot (Fugue Rego Toolkit)”, which is a set of tools that enhances development experience using OPA’s policy engine Rego.
  ○ It aims to provide:
  ○ Just the Rego language implementation rather than the full OPA agent
  ○ Useful tools to debug Rego queries and modules
  ○ Enhanced error messages
  ○ Ease of extending and experimenting with different language feature

READMEs and documentation are not part of container images (unfortunately), but registries typically support documentation against repositories. This tool helps with synchronisation content for Docker Hub, Quay and Harbor registries.

• Docker CLI plugin “docker-pushrm” GitHub page. It provides the docker pushrm (or “push readme”) command to Docker.
• It pushes the README file from the current working directory to the container registry server. On the container registry server, it appears as a repository description in the web interface.

Both AWS and Azure have lots of overlapping services, but if you know one but are using the other how can you navigate the large service catalog? A2a provides a simple tool to help. GCP support planned too.

• OSS CLI tool “A2A *1 “ GitHub page.
• It provides service mapping between Azure and AWS.

How about those articles? Do you have any interest in any?

Actually, I have some contents which I can not digest at this stage, I’ll make use of this aide-memoire and links for catching-up for myself too.

Bye now!!

Yoshiki Fujiwara