Adapt RUM server onboarding to include httpd

[pablomartinezbernardo]

What does this PR do? What is the motivation?

• Add instructions on how to onboard with injection in the server for RUM
• Small changes in the already existing content for clarity

Merge instructions

Merge readiness:

• Ready for merge

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Additional notes

[github-actions]

Preview links (active after the build_preview check completes)

Modified Files

• https://docs-staging.datadoghq.com/pmartinez/rum-httpd/real_user_monitoring/browser/setup/server

[allspain]

Does HTTPD support allowedTracingUrls and excludedActivityUrls? If so we should edit the NGINX line to include HTTPD

[allspain]

There's a paragraph towards the bottom of the page that says:

Content compression by upstream server: If NGINX is acting as a proxy and the upstream server has content compression (like gzip, zstd, or Brotli) enabled, the module may not inject RUM. Ensure that content compression is disabled on the upstream server and configure NGINX to compress the content.

Should this be just NGINX or any of the webservers?

[rtrieu]

Created DOCS-10037 for more in-depth review.

[pablomartinezbernardo]

There's a paragraph towards the bottom of the page that says:

Content compression by upstream server: If NGINX is acting as a proxy and the upstream server has content compression (like gzip, zstd, or Brotli) enabled, the module may not inject RUM. Ensure that content compression is disabled on the upstream server and configure NGINX to compress the content.

Should this be just NGINX or any of the webservers?

It applies to all because they can all be configured as reverse proxies. It also feels redundant with the section above that reads "If proxying compressed traffic...". WGDYT @rtrieu ?

[rtrieu]

Some minor feedback for your review. But otherwise looks good!

[rtrieu]

There's a paragraph towards the bottom of the page that says:
Content compression by upstream server: If NGINX is acting as a proxy and the upstream server has content compression (like gzip, zstd, or Brotli) enabled, the module may not inject RUM. Ensure that content compression is disabled on the upstream server and configure NGINX to compress the content.
Should this be just NGINX or any of the webservers?

It applies to all because they can all be configured as reverse proxies. It also feels redundant with the section above that reads "If proxying compressed traffic...". WGDYT @rtrieu ?

I think you are right that this is repetitive. I'll push a commit with a suggestion to reconcile these two.

[pablomartinezbernardo]

@rtrieu what was your intention behind this line? As of right now it is a bit confusing for me, as it sounds like we're recommending to enable content compression, which shouldn't have an impact on our solution either way.

[rtrieu]

@pablomartinezbernardo my intention was to consolidate this section with the information that was previously under Troubleshooting. We can change it back if this is confusing.