Possibility to trigger re-initialization of component?

Is it somehow possible to trigger the (re)-initialization of a component via an automation?

Reason is that for example my plex server is not always running therefore the initialisation of the plex sensor component and the plex media server component often fails upon restarting.

Another sensor failing initialisation when the respective host is down is glances - so there as well I would like to re-init…

I would like to trigger the initialisation for example after the server was switched on…

Not possible at the moment. There are massive changes to the Home Assistant core underway and this could lead to a more flexible structure that would allow the reloading of platforms like it’s done with automation rules at the moment.

That means that currently all components have to be active and available while starting home-assistant?

I think in general a way of dealing with components appearing/disappearing is necessary.

Yes, it does. There are platforms which are setup even if the device is not working/present/available but that’s the exception. We try to avoid that users end up with multiple platforms/components that not working in their Home Assistant instance.