Installing with docker plugin install no longer works

[jamespickering5-nhs]

What happened:

When attempting to install (on a machine that has never had the plugin installed) using the docker plugin install command documented in the README, Docker fails with:

Error response from daemon: error resolving plugin reference: pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed

The same error occurs when attempting to upgrade (on a machine with a working copy of the plugin) using docker plugin upgrade splunk-logging-plugin.

What you expected to happen:

The plugin was successfully installed

How to reproduce it (as minimally and precisely as possible):

On a machine that has never had the plugin installed, follow the documented install procedure:

docker plugin install splunk/docker-logging-plugin:latest --alias splunk-logging-plugin

Or on a machine that has the plugin installed, upgrade it with:

docker plugin upgrade splunk-logging-plugin

Anything else we need to know?:

The error does not occur when installing other plugins, such as vieux/sshfs.

Additionally, the page for the plugin on Docker hub is currently a 404.

Environment:

• Docker version (use docker version): 27.3.1
• OS (e.g: cat /etc/os-release): Ubuntu 22.04.5 LTS
• Splunk version: Splunk Enterprise 9.0.1
• Others: