What is a PodDisruptionBudget (PDB), and when would you create one?

• A. A PodDisruptionBudget defines the minimum number of available pods during voluntary disruptions, used during node drains or upgrades to maintain availability.
• B. A PDB sets network policies for pods during disruptions.
• C. A PDB configures storage policies.
• D. A PDB defines the image pull policy.

Answer: (A)

A PodDisruptionBudget is a Kubernetes object that defines how many pods can be disrupted during voluntary events, so your application stays available during maintenance. It targets a set of pods (usually by labels) and specifies a threshold like minimum available or maximum unavailable. During actions such as node drains or cluster upgrades, the system will only evict pods if doing so would not drop below that minimum. For example, with five replicas and a minimum available of four, at most one pod can be evicted during a drain. This is precisely what keeps your service online while you perform maintenance. It isn’t about network policies, storage policies, or image pull behavior, which is why the other options don’t fit.