<p>According to <a href="https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/" rel="nofollow noreferrer">https://kubernetes.io/docs/concepts/scheduling-eviction/assign-pod-node/</a></p>
<blockquote>
<p>Note: Pod anti-affinity requires nodes to be consistently labelled, in other words every node in the cluster must have an appropriate label matching topologyKey. If some or all nodes are missing the specified topologyKey label, it can lead to unintended behavior.</p>
</blockquote>
<p>What exactly will happen when there is no topologyKey label? Pods will be placed anywhere and everything will be working or I should expect some errors.</p>

Porok12
<p>After testing, it seems to ignore <code>podAntiAffinity</code> when topologyKey is missing.</p>
