Chapter 3. Recovery for HA applications with RWX storage

PDF

Applications that are using topologyKey: kubernetes.io/hostname or no topology configuration, have no protection against all of the application replicas being in the same zone.

Note

This can happen even with podAntiAffinity and topologyKey: kubernetes.io/hostname in the Pod spec because this anti-affinity rule is host-based and not zone-based.

If this happens and all replicas are located in the zone that fails, the application using ReadWriteMany (RWX) storage takes 6-8 minutes to recover on the active zone. This pause is for the OpenShift Container Platform nodes in the failed zone to become NotReady (60 seconds) and then for the default pod eviction timeout to expire (300 seconds).

Github

Youtube

Twitter

Learn

Try, buy, & sell

Communities

About Red Hat Documentation

We help Red Hat users innovate and achieve their goals with our products and services with content they can trust.

Making open source more inclusive

Red Hat is committed to replacing problematic language in our code, documentation, and web properties. For more details, see the Red Hat Blog.

About Red Hat

We deliver hardened solutions that make it easier for enterprises to work across platforms and environments, from the core datacenter to the network edge.