How to manage units
See also: Unit
This document demonstrates various operations that you can perform on a unit.
Units are also relevant when adding storage or scaling an application. See How to manage storage and How to manage applications.
Contents:
- Add a unit
- Show details about a unit
- List a unit’s resources
- Show the status of a unit
- Set the meter status on a unit
- Mark unit errors as resolved
- Remove a unit
Add a unit
See also:
juju add-unit
To add a unit, use the add-unit command followed by the application name:
juju add-unit mysql
By using various command options, you can also specify the number of units, the model, the kind of storage, the target machine, etc.
Show details about a unit
See also:
juju show-unit
To see more details about a unit, use the show-unit command followed by the unit name:
juju show-unit mysql/0
By using various options you can also choose to get just a subset of the output, a different output format, etc.
List a unit’s resources
See also:
juju resources
To see the resources for a unit, use the resources command followed by the unit name. For example:
juju resources mysql/0
Show the status of a unit
See also:
juju status
To see the status of a unit, use the status command:
juju status
This will show information about the model, along with its machines, applications and units. For example:
Model Controller Cloud/Region Version SLA Timestamp
tutorial-model tutorial-controller microk8s/localhost 2.9.34 unsupported 12:10:16+02:00
App Version Status Scale Charm Channel Rev Address Exposed Message
mattermost-k8s .../mattermost:v6.6.0-20.04... active 1 mattermost-k8s stable 21 10.152.183.185 no
postgresql-k8s .../postgresql@ed0e37f active 1 postgresql-k8s stable 4 no Pod configured
Unit Workload Agent Address Ports Message
mattermost-k8s/0* active idle 10.1.179.151 8065/TCP
postgresql-k8s/0* active idle 10.1.179.149 5432/TCP Pod configured
Set the meter status on a unit
See also:
juju set-meter-status
To set the meter status on a unit, use the set-meter-status command followed by the unit name. For example:
juju set-meter-status myapp/0
Mark unit errors as resolved
See also:
juju resolved
To mark unit errors as resolved, use the resolved command followed by the unit name or a list of space-separated unit names. For example:
juju resolved myapp/0
Remove a unit
See also:
juju remove-unit, Removing things reference
To remove individual units instead of the entire application (i.e. all the units), use the remove-unit command followed by the unit name. For example, the code below removes unit 2 of the PostgreSQL charm.
juju remove-unit postgresql/2
In the case that the removed unit is the only one running, the corresponding machine will also be removed, unless any of the following is true for that machine:
- it was created with juju add-machine
- it is not being used as the only controller
- it is not hosting Juju-managed containers (KVM guests or LXD containers)
It is also possible to remove multiple units at a time by passing instead a space-separated list of unit names:
juju remove-unit mediawiki/1 mediawiki/3 mediawiki/5 mysql/2
To also destroy the storage attached to the units, add the --destroy-storage option.
As a last resort, use the --force option (in v.2.6.1).
Last updated 6 months ago.