diff --git a/doc/examples/kea4/cassandra.json b/doc/examples/kea4/cassandra.json
index a7595d56b6..96936fbb8b 100644
--- a/doc/examples/kea4/cassandra.json
+++ b/doc/examples/kea4/cassandra.json
@@ -49,10 +49,36 @@
       "tcp-nodelay": true,
 
       // This parameter configures consistency level. The default is "quorum".
+      // Supported values:
+      // - any
+      // - one
+      // - two
+      // - three
+      // - quorum
+      // - all
+      // - local-quorum
+      // - each-quorum
+      // - serial
+      // - local-serial
+      // - local-one
+      // See https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlConfigConsistency.html for more details.
       "consistency": "quorum",
 
       // This parameter configures serial consistency level which manages
       // lightweight transaction isolation. The default is "serial".
+      // Supported values:
+      // - any
+      // - one
+      // - two
+      // - three
+      // - quorum
+      // - all
+      // - local-quorum
+      // - each-quorum
+      // - serial
+      // - local-serial
+      // - local-one
+      // See https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlConfigSerialConsistency.html for more details.
       "serial-consistency": "serial"
   },
 
diff --git a/doc/examples/kea6/cassandra.json b/doc/examples/kea6/cassandra.json
index bf7c2f2c85..8264c9cf1c 100644
--- a/doc/examples/kea6/cassandra.json
+++ b/doc/examples/kea6/cassandra.json
@@ -48,10 +48,36 @@
       "tcp-nodelay": true,
 
       // This parameter configures consistency level. The default is "quorum".
+      // Supported values:
+      // - any
+      // - one
+      // - two
+      // - three
+      // - quorum
+      // - all
+      // - local-quorum
+      // - each-quorum
+      // - serial
+      // - local-serial
+      // - local-one
+      // See https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlConfigConsistency.html for more details.
       "consistency": "quorum",
 
       // This parameter configures serial consistency level which manages
       // lightweight transaction isolation. The default is "serial".
+      // Supported values:
+      // - any
+      // - one
+      // - two
+      // - three
+      // - quorum
+      // - all
+      // - local-quorum
+      // - each-quorum
+      // - serial
+      // - local-serial
+      // - local-one
+      // See https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlConfigSerialConsistency.html for more details.
       "serial-consistency": "serial"
   },
 
diff --git a/doc/guide/dhcp4-srv.xml b/doc/guide/dhcp4-srv.xml
index e78bc73dc9..6cca31464f 100644
--- a/doc/guide/dhcp4-srv.xml
+++ b/doc/guide/dhcp4-srv.xml
@@ -598,12 +598,20 @@ The default value for Cassandra is 2000 ms.
       <listitem><simpara>
         <command>consistency</command> - configures consistency level.
         The default is "quorum".
+        Supported values: any, one, two, three, quorum, all, local-quorum, each-quorum,
+        serial, local-serial, local-one.
+        See <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlConfigConsistency.html">Cassandra consistency</link>
+        for more details.
       </simpara></listitem>
 
       <listitem><simpara>
         <command>serial-consistency</command> - configures serial consistency
         level which manages lightweight transaction isolation. The default is
         "serial".
+        Supported values: any, one, two, three, quorum, all, local-quorum, each-quorum,
+        serial, local-serial, local-one.
+        See <link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="https://docs.datastax.com/en/cassandra/3.0/cassandra/dml/dmlConfigSerialConsistency.html">Cassandra serial consistency</link>
+        for more details.
       </simpara></listitem>
 
     </itemizedlist>