[Fleet] Update doc for preconfiguration

[nchaulet]

Description

The doc for preconfigured object (policy, outputs, ...) as not been updated since a long time and is out of date with what we currently support.

Link to the doc:

https://www.elastic.co/guide/en/kibana/master/fleet-settings-kb.html

Source of the doc:

https://github.com/elastic/kibana/blob/main/docs/settings/fleet-settings.asciidoc

We should:

• In outputs support for logstash and add missing properties (ssl) is_default_monitoring
• Add Fleet server hosts xpack.fleet.fleetServerHosts
• Add proxy xpack.fleet.proxy

[elasticmachine]

Pinging @elastic/fleet (Team:Fleet)

[jen-huang]

FYI @karenzone, just transferred this one here.

[kilfoyle]

Hi @nchaulet

I'd like to add these missing settings to the docs but I'll need some help.

We added the is_default_monitoring setting already via elastic/kibana#154247

For the other settings xpack.fleet.fleetServerHosts and xpack.fleet.proxy can you help me with:

• a description of what each setting is
• where I can find the required and optional parameters

I tried looking in the Fleet API docs and I also searched through the code in the Kibana repo, but I was a bit lost. :-)

[nchaulet]

Hi @kilfoyle (here is the schema we use for the config of preconfigured object not obvious to find and neither to read https://github.com/nchaulet/kibana/blob/2dd3a8faf266a8d88e4955cd7dcbe7e3b8f25bb7/x-pack/plugins/fleet/server/types/models/preconfiguration.ts#L89-L116)

for the xpack.fleet.fleetServerHosts we accept an array of object with the following properties

required:
 id: string; // an unique id
 name: string;  // A name for the UI
 host_urls: string array;  // an array of https url 

optionnal:    
  is_default: boolean; // if it's the default fleet server host
  proxy_id: string; // the proxy to use with that fleet server host

for xpack.fleet.proxy we accept an array of object with the following properties

required:
  id: string;
  name:string;
  url: string // the proxy url

optionnal:
    proxy_headers: object [key string, value string] a map of headers to use with the proxy
    certificate_authorities: string;
    certificate: string;
    certificate_key: string;

we also support the proxy_id for output that allow to use a proxy with an output

Let me know if you have more questions

[kilfoyle]

The Fleet settings in Kibana page is now updated with the is_default_monitoring, xpack.fleet.fleetServerHosts, and xpack.fleet.proxy settings.