Add at least something about SSO

Author: tswfi

src/sysops/sso.md

@@ -0,0 +1,5 @@
+# SSO (Keycloak)
+
+hacklab.fi runs a [Keycloak](https://www.keycloak.org/) instance and every lab has their own realm on the instance.
+
+At least Tampere, Akaa and Vaasa use SSO extensively for logging into Hacklab services like [Nextcloud](https://nextcloud.com/), [DokuWiki](DokuWiki), Website and [Matrix Chat](https://chat.hacklab.fi/) and use [Mulysa](https://github.com/tampereHacklab/mulysa/) as their Identity Provider.