Command 'enable-ha'

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.