We will no longer support CentOS, Fedora, and Opensuse as installation targets. These are not actively maintained by anyone with commit rights and occasionally cause issues for users as they are not tested during the release process.
Rather than have subpar support for an untested operating system, we're removing support for them completely. Users of these operating systems should take a look migration to the docker-based installation method, which will always be tested and supported by the project.
Additionally, drop support for Debian 9 as it is now EOL.
This makes the installation a bit more secure by ensuring a user does not accidentally expose a way for unauthorized users to add new ssh keys to the system.
Additionally, this removes the extra HOSTNAME file to make the initial install process easier (that file was not modifiable by any dokku commands.
Closes#2247
As of April 2021, it will no longer be an LTS release, and thus us supporting it will increase maintenance burdens.
Also switch CI to use 18.04, so as to test what we currently support.
Closes#4505
While the latest packages may continue to work on other releases, we will no longer officially support these releases, nor will we distribute packages.
This script previously ran through the docker installation process with the edge channel on each run. Instead, we only run the docker installation if docker is not available. In addition, we force set the channel to stable, ensuring the script installs the correct channel for stable docker installations.
Closes#3269
While I do not agree with _every_ style change, this will force Dokku to have consistent formatting across all shell scripts, which is arguably a Good Thing™.
The command used to reprocess everything is:
```shell
shfmt -l -bn -ci -i 2 -w .
```
This allows us to force another plugin as the default vhost implementation, or disable it altogether in favor of some higher-level proxy implementation, such as one that integrates with service discovery.
The centos rpm packages should be installable on centos once this is merged and released. However, Dokku will not maintain an Rhel-specific repository as there is no way for us to feasibly test it.
Closes#3046
