Use service discovery in backends

Integrate the failover improvements with our back ends. The DNS domain
used in the SRV query is always the SSSD domain name.

Please note that this patch changes the default value of ldap_uri from
"ldap://localhost" to "NULL" in order to use service discovery with no
server set.

1 files changed, 36 insertions, 0 deletions

diff --git a/src/man/include/service_discovery.xml b/src/man/include/service_discovery.xml
new file mode 100644
index 00000000..16d016ea
--- /dev/null
+++ b/src/man/include/service_discovery.xml
@@ -0,0 +1,36 @@
+<refsect1 id='service_discovery'>
+    <title>SERVICE DISCOVERY</title>
+    <para>
+        The service discovery feature allows back ends to automatically
+        find the appropriate servers to connect to using a special DNS
+        query.
+    </para>
+    <refsect2 id='configuration'>
+        <title>Configuration</title>
+        <para>
+            If no servers are specified, the back end automatically
+            uses service discovery to try to find a server. Optionally,
+            the user may choose to use both fixed server addresses
+            and service discovery by inserting a special keyword,
+            <quote>_srv_</quote>, in the list of servers. The order
+            of preference is maintained. This feature is useful if, for
+            example, the user prefers to use service discovery whenever
+            possible, and fall back to a specific server when no servers
+            can be discovered using DNS.
+        </para>
+    </refsect2>
+    <refsect2 id='domain_name'>
+        <title>The domain name</title>
+        <para>
+            The name of the SSSD domain is used as the domain part of the
+            service discovery DNS query.
+        </para>
+    </refsect2>
+    <refsect2 id='reference'>
+        <title>See Also</title>
+        <para>
+            For more information on the service discovery mechanism,
+            refer to RFC 2782.
+        </para>
+    </refsect2>
+</refsect1>