Use cluster name in alloy metrics

[petewall]

Request

When --cluster.name is specified, use that in relevant metrics, like alloy_config_hash

Use case

This will help differentiate between configs from the same alloy cluster or different alloy clusters.

[f9n]

For those who need it, you can add cluster label for all metrics as below until this development arrives. We deploy the Alloy to virtual machines. While deploying Alloy, we add the CLUSTER_IDENTIFIER environment variable to the service definition with ansible role.

prometheus.exporter.self "default" {}

prometheus.scrape "selfmonitor" {
    targets = concat(
      prometheus.exporter.self.default.targets,
    )

    forward_to = [prometheus.relabel.selfmonitor.receiver]
}

prometheus.relabel "selfmonitor" {
    forward_to = ["..."]

    rule {
      action        = "replace"
      target_label  = "cluster"
      replacement   = env("CLUSTER_IDENTIFIER")
    }
}

[github-actions]

This issue has not had any activity in the past 30 days, so the needs-attention label has been added to it.
If the opened issue is a bug, check to see if a newer release fixed your issue. If it is no longer relevant, please feel free to close this issue.
The needs-attention label signals to maintainers that something has fallen through the cracks. No action is needed by you; your issue will be kept open and you do not have to respond to this comment. The label will be removed the next time this job runs if there is new activity.
Thank you for your contributions!