• By Dylan Stephano-Shachter
Channel Version Revision Published Runs on
latest/stable 36 36 21 Oct 2022
Ubuntu 20.04
latest/candidate 36 36 21 Oct 2022
Ubuntu 20.04
latest/beta 36 36 21 Oct 2022
Ubuntu 20.04
latest/edge 37 37 22 Nov 2022
Ubuntu 20.04
1.0/stable 36 36 21 Oct 2022
Ubuntu 20.04
1.0/candidate 36 36 21 Oct 2022
Ubuntu 20.04
1.0/beta 36 36 21 Oct 2022
Ubuntu 20.04
1.0/edge 36 36 21 Oct 2022
Ubuntu 20.04
juju deploy alertmanager-k8s
Show information


Forming a cluster

Alertmanager supports clustering and all you need to do to create/update a cluster is to rescale the application. This can be done in two ways.

Let’s say we have one alertmanager unit running and we want to scale the deployment to three units.

With juju add-unit we can achieve that using the --num-units argument and the number of units we want to add:

juju add-unit alertmanager-k8s --num-units 2

or using juju scale-application and the total number of units we want:

juju scale-application alertmanager-k8s 3

Regardless of which of the two options you use, juju status --relations --color will show you the status of the cluster.

Internally, HA is achieved by providing each Alertmanager instance at least one IP address of another instance. The cluster would then auto-update with subsequent changes to the units present.


Pebble plan

Cluster information is passed to Alertmanager via --cluster.peer command line arguments. This can be verified by looking at the current pebble plan:

> $ juju exec --unit alertmanager-k8s/0 -- \
  PEBBLE_SOCKET=/charm/containers/alertmanager/pebble.socket \
  pebble plan

        summary: alertmanager service
        startup: enabled
        override: replace
        command: alertmanager --config.file=/etc/alertmanager/alertmanager.yml --storage.path=/alertmanager --web.listen-address=:9093 --cluster.listen-address= --cluster.peer= --cluster.peer=


To manually verify a cluster is indeed formed, you can query the alertmanager HTTP API directly:

> curl -s $ALERTMANAGER_IP:9093/api/v1/status \
  | jq '.data.clusterStatus.peers[].address'

Help us improve this documentation

Most of this documentation can be collaboratively discussed and changed on the respective topic in the doc category of the Charmhub forum. See the documentation guidelines if you’d like to contribute.

Last updated 3 months ago. Help improve this document in the forum.