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+#Baïkal
+
+Baïkal is a server for calendars and address book, which used CalDav and CardDav protocol. Baïkal can be synced with a lot of client like Thunderbird + Lightning.
+
+### Web admin connection
+In SSO portal, click on "Baïkal", a link lead to a web page showing a message saying that the service is running. To acces the admin web page, add `/admin` to the URL. For example:
+
+https://domain.org/baikal/admin
+
+The user name specified is "admin" followed by the specific password choosen at Baïkal installation procedure.
+
+### Connection with Thunderbird + Lightning
+
+Add a new agenda with type "Network" and "CalDAV"
+
+The new URL to add is :
+
+https://domain.org/baikal/cal.php/calendars/username/default
+
+Be careful to replace "domain.org" by your own domain and the "username" by your user name.
+
+
+### Connection to AgenDAV
+
+AgenDAV is a web client for using your calendars. It's packaged for Yunohost and you can used it after installing Baïkal.
+
+AgenDAV is already connected to Baïkal, any other configuration is necessary. If you create a new entry in Thunderbird + Lightning calendar, refresh your AgenDAV page is enough to see your modifications.
+
+AgenDAV also allows you to create a new calendars very easily.
+