Follow up on collector deployment

[mhausenblas]

In #2498 we parked a few things that should be addressed ASAP in a follow-up PR. They are:

Changes for follow up PR for #2498

In agent.md

Expand on the cons for the agent pattern, that is, flesh out the following:

• Scalability (human and load-wise)
• Inflexible

In best-practices.md

• replace Jaeger exporter with OTLP exporter
• simplify by configuring both exporters for the same pipeline in metrics/prod
• make sure we use attributes covered by the semantic conventions across the doc

Replace:

processors:
  attributes:
    actions:
      - key: cluster
        value: eu-west-1
        action: upsert
  metricstransform:
    transforms:
      - include: otelcol_process_uptime
        action: update
        operations:
          - action: add_label
            new_label: cluster
            new_value: eu-west-1

With:

transform:
  error_mode: ignore
  trace_statements:
    - context: span
      statements:
        - set(attributes["cluster"], "eu-west-1") 
  metric_statements:
    - context: datapoint
      statements:
        - set(attributes["cluster"], "eu-west-1") where metric.name == "otelcol_process_uptime

In collector/_index.md

Replace #when-to-use-a-collector with one that calls out all the deployment patterns and mentions that there is one for no collector and what the advantages/disadvantages are.

[mhausenblas]

In gateway.md update the note that says LB exporter only supports traces (it also supports logs).

[theletterf]

@mhausenblas What's missing to close the issue?

[mhausenblas]

@theletterf as per above. We might need to pause/archive/attic it for now, I won't have cycles for it in the near future

[svrnm]

Thanks for clarification, I removed the assignment and added a help wanted label such that people can pick it up

[Ananyasinha13]

Can you assign this issue to me.

[Ananyasinha13]

Can you share me the repo link

[svrnm]

Can you assign this issue to me.

We do not assign issues, please go ahead and provide a PR for this issue if you want to work on it, it can be an early draft or an incremental change, depending on the complexity. Repo URL is https://github.com/open-telemetry/opentelemetry.io