Recently while scrolling on Twitter I saw this tweet by John Nunemaker.

Who knows things about multi-tenant SSO (SAML or Okta, etc.) + ruby on rails and is willing to do a call with me? Happy to barter or pay.

— John Nunemaker (@jnunemaker) May 18, 2023

Since we had implemented multi-tenant SSO at PagerTree, I thought I could help out. After all, I claimed it was only ~100 lines of code (turns out it is closer to 400). After sharing a raw gist, I realized a blog post would be more helpful to the community.

In this blog post, I want to describe how we implemented multi-tenant SSO at PagerTree to work with any SAML2 identity provider (Okta, Google, Azure, etc.).

TL;DR​

Fly.io Postgres stuck in read-only mode​

• During the migration to the Fly.io platforms v2, the provided command (migrate-to-v2) times out if a Postgres cluster doesn't replicate and failover fast enough.
• The migrate-to-v2 command first puts the database in a read-only state. When the timeout occurs, the command fails to remember to put the database back in a writable state.
• After the database is read-only, new and existing connections will not be able to write to the database. This caused PagerTree to functionally fail for approximately 45 minutes on July 30, 2023 from 00:30 -> 01:15 UTC.
• The Postgres cluster can be put back into a writable state with the following commands:

# connect to postgres psql
fly postgres connect -a <postgres_fly_app_name>
# This will show false for the postgres DB
SHOW default_transaction_read_only; 
# connect to the production db
\connect <production_db_name>
# This will now show the root cause of issue
SHOW default_transaction_read_only;
# the following command will only work for the current connection
SET default_transaction_read_only TO off;
# connect back to postgres
\connect postgres
# fix the real problem
alter database <production_db_name> set default_transaction_read_only=off;

Prometheus is an open-source monitoring and alerting toolkit that has gained significant popularity in DevOps and systems monitoring. At the core of Prometheus lies PromQL (Prometheus Query Language), a powerful and flexible query language used to extract valuable insights from the collected metrics. In this guide, we will explore the basics of PromQL and provide query examples for an example use case.

PowerShell is a powerful scripting language and command-line shell that is designed specifically for system administration and automation tasks in Windows environments. Whether you're a seasoned sysadmin or just starting with PowerShell, having a cheat sheet of essential commands at your fingertips can greatly enhance your productivity. In this blog post, we will cover some fundamental PowerShell commands, starting from the basics and gradually progressing to more advanced concepts.

A new version of the PagerTree iPhone app is available today that adds support for Apple's Critical Alerts.

Critical Alerts are special notifications that bypass the device's mute switch, focus, and do not disturb settings to generate an audible notification in emergency situations. Critical Alerts are only available to applications that have applied and been approved by Apple.

In this article I will highlight the 6 key docker commands I use on a daily basis while using Docker in the real world.

By no means is this an extensive list of docker commands. I kept it short on purpose so you could use it as a quick reference guide. I’ve also omitted the topic of building images and the commands that are associated with that.

At the bottom of the page, I’ll also put some good links to other Docker resources I like or frequently use as well as other PagerTree cheat sheet documents. For a full crash course, check out our Learn Docker Series!

Data Breach ​

You have identified a data breach, now what?

Your Incident Response Playbook is up to date. You have drilled for this, you know who the key players on your team are and you have their home phone numbers, mobile phone numbers, and email addresses, so you get to work. It is seven o’clock in the evening so you are sure everyone is available and ready to respond, you begin typing “that” email and making phone calls, one at a time.

In this tutorial, I will show you how to build and deploy a Jekyll static site to AWS S3 + Cloudfront using GitHub Actions. At PagerTree we use GitHub Actions to automate the building and deploying of our marketing site pagertree.com.

Today, we are excited to announce PagerTree now officially supports maintenance windows! Long overdue (technically from our 2019 roadmap), with maintenance windows it’s now easier than ever to suppress alerts from integrations during specific time periods.

Maintenance Windows are available on our Pro and Elite pricing plans. If you don’t already have an account, sign up for a free-trial now.

Rails 7 has introduced Active Record Encryption, functionality to transparently encrypt and decrypt data before storing it in the database. This is awesome news for any developer who has ever had to encrypt data before storing it.

Now arriving in Rails 7: Active Record Encryption, created by @jorgemanru. Designed for, and extracted from, @heyhey email. https://t.co/PMW0ROojX1

— Jeremy Daer (@bitsweat) April 1, 2021

In this guide, I will walk you through an example to migrate from away from using attr_encrypted gem to the new Rails 7 Active Record encrypts. We will do this using strong migrations and also maintain the ability to perform a database rollback without data loss.