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Keystone supports both tokens and ec2 credentials simultaneously, but as 
far as I can tell, will only do a single token format (uuid, pki/z, 
fernet) at a time. Is it possible or advisable to configure keystone to 
issue multiple token formats? For example, I could configure two 
keystone servers, each using a different token format, so depending on 
endpoint used, I could get a uuid or pki token. Each service can use 
either token format, so is there a conceptual or implementation issue 
with this setup?
Thanks,
Reza