Right now my OpenAPI 2.0 YAML file has only one host URL:
host: petstore.test.com
basePath: /
Can I use multiple hosts like this?
host1: petstore.test.com
host2: petstore1.test.com
host3: petstore2.dev.com
OpenAPI 2.0 (Swagger 2.0) only supports a single host with multiple schemes (HTTP/HTTPS/etc.), so you can effectively have two hosts that only vary in the scheme:
host: petstore.test.com
schemes:
- http
- https
The latest version, OpenAPI 3.0, supports multiple hosts with different schemes and base paths:
servers:
- url: https://petstore.prd.com
description: Production server
- url: {scheme}://petstore.dev.com/subpath
description: Development server
templates:
scheme:
enum:
- http
- https
default: https
For more examples, see this answer.