Document open telemetry ingestion using forward protocol

[yogzblr]

Is your feature request related to a problem? Please describe.
There is no clear documentation to send open telemetry via fluentbit in HA mode via fluentd or another fluentbit to a hub aggregator like vector

Describe the solution you'd like
A documented and supported solution to do this that everyone can use

Describe alternatives you've considered
We dont want to use a load balancer to provide ingestion with HA

The POC repo is here
https://github.com/yogzblr/fb-forward-poc

The readme mentioned what was tested. Can this get into official documentation

[cosmo0920]

Thank you for your feedback.

Fluent Bit supports forwarding OTLP data in HA setups without a load balancer, but this pattern is undocumented.
Critical options like retain_metadata_in_forward_mode and OTLP metadata key mappings are required to preserve trace context, yet are not described in official docs.
I supposed that this POC demonstrates a fully working, supported architecture that should be documented as a reference configuration.

Could you process further documentation, @eschabell ?
This could be useful addition in our official document if possible to add.

[patrick-stephens]

I'm going to move this from Fluent Bit implementation to Fluent Bit docs repo I think, mostly because I can then assign it to @eschabell explicitly but also because it is a docs issue rather than an implementation one.

[eschabell]

Adding to my todo list, thanks for the issue @yogzblr

[eschabell]

@yogzblr would you like to provide a document PR for this? I'd be happy to share this on it's own page as a new section on reference architectures... so create it's own page, sound like fun to you?