A Case Study on Runtime Verification of a Continuous Deployment Process

TL;DR

Through the case study, it was found that FluxCD did not always detect a new image within five minutes after it was pushed to GHCR, whereas it always did so within ten minutes in the collected logs.

Abstract

We report our experience in applying runtime monitoring to a FluxCD-based continuous deployment (CD) process. Our target system consists of GitHub Actions, GitHub Container Registry (GHCR), FluxCD, and an application running on Kubernetes. We monitored its logs using SyMon. In our setting, we regard a deployment update as detected when FluxCD's polling log resolves the latest image tag. Through the case study, we found that FluxCD did not always detect a new image within five minutes after it was pushed to GHCR, whereas it always did so within ten minutes in the collected logs. Moreover, our results show that SyMon is fast enough for near-real-time monitoring in our setting.

Figures (1)

• Figure 1: Outline of the target system. Events observed by the monitor correspond to the actions shown by thick arrows.