The information in this doc is based on Juju version 3.5.6, and may not accurately reflect other versions of Juju.
Summary
Ensure that sufficient controllers exist to provide redundancy.
Options
| Flag | Default | Usage |
|---|---|---|
-B, --no-browser-login |
false | Do not use web browser for authentication |
-c, --controller |
Controller to operate in | |
--constraints |
Additional machine constraints | |
--format |
simple | Specify output format (json|simple|yaml) |
-n |
0 | Number of controllers to make available |
-o, --output |
Specify an output file | |
--to |
The machine(s) to become controllers, bypasses constraints |
Examples
Ensure that the controller is still in highly available mode. If there is only 1 controller running, this will ensure there are 3 running. If you have previously requested more than 3, then that number will be ensured.
juju enable-ha
Ensure that 5 controllers are available:
juju enable-ha -n 5
Ensure that 7 controllers are available, with newly created controller machines having at least 8GB RAM.
juju enable-ha -n 7 --constraints mem=8G
Ensure that 7 controllers are available, with machines server1 and server2 used first, and if necessary, newly created controller machines having at least 8GB RAM.
juju enable-ha -n 7 --to server1,server2 --constraints mem=8G
Details
To ensure availability of deployed applications, the Juju infrastructure must itself be highly available. The enable-ha command will ensure that the specified number of controller machines are used to make up the controller.
An odd number of controllers is required.