vaultStatus - Active node: pod doesnt exist any more about vault-operator HOT 1 OPEN

Apparently you have to unseal again in order to replace the active node :/

If you run Vault with two pods, you have to unseal both
You could verify if both are unsealed if you check the vaultStatus
it should look like this:

$ kubectl -n kube-system get vault vault -o json
...
        "vaultStatus": {
            "active": "vault-98bd96bd8-8cxt9",
            "sealed": null,
            "standby": [
                "vault-98bd96bd8-jr7gf"
            ]
        }
...

In this case it fails over properly.

from vault-operator.