Question:

Is SHA-2 functionality supported in Vault? 

Answer:

Yes. SHA-2 functionality is supported in Vault by selecting the SHA-256 option in the Vault SAML Profile.

The proper way to test this is to do the following:

1. Create a new SAML Profile that uses the SHA-256 algorithm.
2. Load the new certificate into a test environment on the customer's internal network.
3. Point the new SAML profile to this certificate.

Related Documentation:

Vault Single Sign-On Documentation: About Signature & Digest Algorithm