How to rename label within a metric in Prometheus

Question

I have a query:

node_systemd_unit_state{instance=\"server-01\",job=\"node-exporters\",name=\"kubelet.service\",state=\"active\"} 1

I want the l

Answer 1

you can use the label_replace function in promQL, but it also add the label, don't replace it

label_replace(
  , "", "$1", "", "(.+)"
)

label_replace(
node_systemd_unit_state{instance="server-01",job="node-exporters",name="kubelet.service",state="active"},
"unit_name","$1","name", "(.+)"
)

So, to avoid the repetition you can add:

sum(label_replace(
    node_systemd_unit_state{instance="server-01",job="node-exporters",name="kubelet.service",state="active"},
    "unit_name","$1","name", "(.+)"
    )
)by(unit_name)