Clarification on the steps for the external gateways in the upgrading guide from 2.5 to 2.6

It is not clear in the step 1 of 2.9. Migrate from WildcardRouter to Zync Route Management whether is necessary to perform this step if you use the built-in gateways.

In 3scale 2.6 it has been introduced the concept/configuration option "APIcast hosted" and "APIcast self-managed". APIcast hosted are apicast-staging/production deployed in the 3scale deployment itself. APIcast self-managed is a gateway deployed separately, in the same project, on another project or outside OpenShift. Before 2.5 all gateways (built-in or self-managed) used the same configuration option in 3scale (3scale managed). This is important because depending of the option chosen Zync will create the routes or will delete them/not generate them.

The request is to add :

• An explanation of the difference between hosted and self-managed gateways in On-Premises and that this has been introduced in 2.6 and above.
• The fact that changing to a self-managed gateway Zync will delete the existing routes and will clear out the URLs that you have in the admin portal. You have to recreate them manually.
• The fact that if you changed from hosted to self-managed and revert the change to hosted, the Public Base URLs will be recreated automatically with a standard URL. If you had a custom Public Base URL and did those changes, the initial URL will be changed for the one that Zync creates. You will have to update the Public Base URls.
• If using path routing, you need to use the self-managed option: https://issues.redhat.com/browse/THREESCALE-4072
• If using self-managed gateway, there is no need to remove the routes, as you will need to create them manually.
• In step 1 of 2.9 add a comment similar to this: This is for external gateways only. If you are using the built-in gateways deployed as part of the 3scale installation you DO NOT need to perform this step. (During the migration all services will be migrated to "hosted" unless you change them to slef-managed with the curl requests shared in this step 1).

It can be confusing for some customers understand the configuration options, the implications that it has, if they are using path routing the need to use self-managed option and wonder if the step 1 of the chapter 2.9 is required.