is it possible to enable SSO based login for OSS GRAFANA version? We saw the docs, SSO is not active for OSS version. Is there a way to enable SSO. We tried using NGINX as the reverse proxy layer to define the SAML configuration.
Yes, OSS Grafana supports SSO - Open ID Connect SSO protocol - https://grafana.com/docs/grafana/latest/auth/generic-oauth/
If you need native SAML SSO protocol support, then you need Enterprise Grafana.
Of course you may try to hack it also with OSS Grafana. For example with Grafana with auth proxy authentification and some SAML auth proxy (e.g. Apache with Shiboleth) in front of Grafana - but that needs proper skill to set up everything properly.