I am attempting to configure single sign on in our org. We are using Azure DevOps as the provider. We need to test in our sandbox before we deploy this feature to production. We have single sign on enabled in production and now in our full sandbox. I configured Single Sign On. Now, I'm attempting to go to My domain to set up the Authentication Configuration. When I do this, the SSO I configured isn't there. We are configuring this for our community portal users. We are using federation Ids. Please help.
The Authentication Service section in My Domain shows up the SSO configurations only if SAML is enabled in your Org and that My Domain is deployed. Refer to the below excerpt from the documentation for Add Identity Providers to a Login Page (emphasis mine):
If you’ve enabled single sign-on and configured SAML, or set up external authentication providers as Auth. Providers in Setup, you can provide links to these identity providers on your My Domain subdomain’s login page
You must deploy My Domain before editing authentication configuration settings.
To enable SAML, you can find details on the documentation, screenshot below.
Once you enable the SAML, you should be able to view the SSO configuration on My Domain page under Authentication Service when you click on Edit button.