@mark-robustelli thanks Mark.
All domains will be sub-domains of the main domain name, but for this staging system, we are using 2026.domain.com and 2026-tenant1.domain.com, 2026-tenant2 etc.
Logins work successfully without the idphint on a per tenant basis but we want all tenants to use the common master tenant (via SSO) as the login, because many users will be members across multiple tenants and their data can be common across tenants.
The auth server uses auth.domain.com
We have the master tenant and sub tenants in FusionAuth. We have the master application and sub-tenant applications for each tenant.
A tenant application has an authorized redirect like 2026-tenant1.domain.com/callback and currently no request origin (I have tried adding this for sub-tenant and master tenant together). I've tried adding the sub-tenants as authorized origins on the master tenant.
There's nothing extra configured on the FusionAuth tenants.
Under settings, Identity Providers, we have an OIDC provider pointing back to the master app in the master tenant. We do see the button to login with master tenant on a sub-tenant (if no idphint is set).
All sub-tenant applications are enabled for this provider (with create reg), I also have the sub-tenants added in this IP and have tried without. Managed domains is blank. Not using the POST method.
Auth endpoints have been manually set (because FusionAuth couldn't self-discover?!) like so:
https://auth.domain.com/oauth2/authorize,
https://auth.domain.com/oauth2/token,
https://auth.domain.com/oauth2/userinfo
There's no groups configured.
Hosting wise, FusionAuth is a Docker container on the same server with the main app and sub-tenants behind a Traefik 2 proxy which is also behind Cloudflare and each site has its own LetsEncrypt SSL cert via Traefik.
Direct login to the master tenant is successful but not via a sub-tenant.
Grok suggests it's a CORS issue. My filter was not enabled. I also tried enabled (current) and allowed all methods with (and without) wildcard origins.
As mentioned, the login is recorded on FusionAuth, it just seems to fail on the callback process via master..
The master login URL when called via a sub-tenant shows the master tenant as the callback URL. I've tried adding the sub-tenant callback as authorised in the master tenant.
I think that's everything..