Deciding where workloads run.
WHAT THE SCHEDULER USES
Resource requests Node capacity Constraints you specify
WHAT A NODE SELECTOR DOES
Restricts a pod to nodes with a label.
WHERE THAT IS USED
Nodes with particular hardware, or in a particular zone.
WHAT AFFINITY ADDS
Preferences as well as requirements.
WHY PREFERENCES MATTER
A hard requirement that cannot be met leaves the pod pending forever.
WHAT ANTI-AFFINITY DOES
Keeps pods apart.
WHY THAT MATTERS
Several replicas on one node all die when it does.
WHAT TO SET FOR ANYTHING IMPORTANT
Anti-affinity spreading replicas across nodes.
WHAT TAINTS AND TOLERATIONS DO
Reserve nodes for specific workloads.
HOW
A taint repels pods; a toleration permits one to land anyway.
WHERE THAT SUITS
Nodes with expensive hardware Nodes reserved for system components
WHAT A DISRUPTION BUDGET DOES
Limits how many replicas may be unavailable during voluntary operations.
WHY IT MATTERS
Node maintenance otherwise removes every replica at once.
WHAT TO SET
A minimum available, for anything serving traffic.
WHAT TO BE CAREFUL WITH
Budgets so strict that node maintenance cannot proceed.
WHAT TO CHECK WHEN A POD WILL NOT SCHEDULE
Its events, which state the reason.
