From Custom to Open: Scalable Network Probing and HTTP/3 Readiness with Prometheus

The Problem: Legacy Tooling and Its Limitations

Currently, Slack utilizes a hybrid approach to network measurement, incorporating both internal (such as traffic between AWS Availability Zones) and external (monitoring traffic from the public internet into Slack’s infrastructure) solutions. These tools comprise a combination of commercial SaaS offerings and custom-built network testing solutions developed by our internal teams over time. This was a suitable enough solution for our needs.

When we began rolling out HTTP/3 support on the edge, there was a significant challenge that we encountered: A lack of client-side observability.