As Werner Vogels, CTO of AWS, famously said everything fails all the time; containers and pods can and will crash, become corrupted, or maybe even just get accidentally shut off by a clumsy admin poking around on one of the nodes. Strong policy and security practices like enforcing least privilege curtail some of these incidents, but involuntary workload slaughter happens and is simply a fact of operations.

Luckily, Kubernetes provides two very valuable constructs to keep this somber affair all tidied up behind the curtains. Services and replication controllers/replica sets give us the ability to keep our applications running with little interruption and graceful recovery.