httpTokens

Indicates whether a signed token header is required for instance metadata retrieval requests. The values affect the response as follows:

• required – When you retrieve the IAM role credentials, version 2.0 credentials are returned in all cases.

• optional – You can include a signed token header in your request to retrieve instance metadata, or you can leave it out. If you include it, version 2.0 credentials are returned for the IAM role. Otherwise, version 1.0 credentials are returned.

The default setting is optional.