kromogo cluster_age_days calculation

[reefland]

I think you have the wrong calculation for cluster_age_days using:

          - name: cluster_age_days
            query: round((time() - max(kube_node_created{kubernetes_node=~"k8s-[0-9]+"}) ) / 86400)
            suffix: "d"

The max(kube_node_created) would return the value of your newest node member, not your oldest. Thus it returns the number of days since you last added a node. If you want the cluster age in days, then use the min() to get the timestamp of the oldest cluster node.

When I use round((time() - min(kube_node_created)) / 86400) I get 681 which lines up to the age of my oldest cluster node:

$ k get nodes
NAME    STATUS   ROLES                       AGE    VERSION
k3s01   Ready    control-plane,etcd,master   680d   v1.28.5+k3s1
k3s02   Ready    control-plane,etcd,master   654d   v1.28.5+k3s1
k3s03   Ready    control-plane,etcd,master   661d   v1.28.5+k3s1
k3s04   Ready    worker                      427d   v1.28.5+k3s1
k3s05   Ready    worker                      427d   v1.28.5+k3s1
k3s06   Ready    worker                      354d   v1.28.5+k3s1

if I use max() then I get 355 which is the age of the newest node.

[onedr0p]

Thanks for reporting, fixed!