Co-authored by @Carlos Chivardi and @Brian Hall
This blog post is the second of three posts that explains the self-healing check and liveness probe feature of IBM Sterling Integrator Certified Containers (SICC) , running on Red Hat Open Shift (RHOS).
Read the first post here - IBM Sterling Integrator Certified Containers: Self-healing Scenario (Part 1)
This blog post series is divided into these topics:
- SICC Liveness Overview
- How SICC self-healing works
- Benefits of self-healing feature in SICC
In this blog post we will cover the how SICC self-healing works topic.
As per figure 1, the my-release-b2bi-ac-server-0 pod container will have its liveness probe script removed therefore it will not pass its health check. The container will then be replaced by the Kube-Master with a new healthy pod will be created and started.For this, a connection to the pod should be established by accessing the my-release-b2bi-ac-server-0 pod container (See Figure 1).
Figure 2 shows SICC’s my-release-b2bi-ac-server-0 pod container terminal window. By typing the following command, the Application Health check is removed and Kube-Master will have three failed liveness health checks failed:
This will cause termination for the Pod Container. This sequence of events can be seen in the Events tab (See Figure 3). Notice the sequence, where liveness probe fails, then termination is completed and a new ac container is started by pulling from the proper image, but the readiness probe failed because the container is not ready yet.
Figure 4 displays that the new pod container is already started, ready and healthy.
The last part of this blog series will talk about the benefits of this SICC Self-Healing feature. Stay tuned!