[295-min-max-lease-time-configuration-options] Updated documentation

diff --git a/doc/guide/dhcp4-srv.xml b/doc/guide/dhcp4-srv.xml
index 238c34a83adb17ceac53b18e50928abf83569dc7..d2816f9b092c6d40c0e46de717136352a74df2f6 100644 (file)
--- a/doc/guide/dhcp4-srv.xml
+++ b/doc/guide/dhcp4-srv.xml
@@ -229,15 +229,27 @@ use it for 4000 seconds. (Note that integer numbers are specified as is,
 without any quotes around them.) <command>renew-timer</command> and
 <command>rebind-timer</command> are values (also in seconds) that
 define T1 and T2 timers that govern when the client will begin the renewal and
-rebind procedures. <note>Both <command>renew-timer</command> and
-<command>rebind-timer</command> are optional. The server will only send
-rebind-timer to the client, via DHCPv4 option code 59, if it is less than
-valid-lifetime; and it will only send renew-timer, via DHCPv4 option code 58,
-if it is less than rebind-timer (or valid-lifetime if rebind-timer was not
-specified). In their absence, the client should select values for T1 and T2
-timers according to <link xmlns:xlink="http://www.w3.org/1999/xlink"
-xlink:href="http://tools.ietf.org/html/rfc2131">RFC 2131</link>.
-See section <xref linkend="dhcp4-t1-t2-times"/> for more details on
+rebind procedures.
+
+<note>From Kea 1.6.0 the lease valid lifetime is extended from a
+single value to a triplet with minimum, default and maximum values using
+<command>min-valid-lifetime</command>, <command>valid-lifetime</command> and
+<command>max-valid-lifetime</command>. When the client does not specify
+a lifetime the default value is used, when it specifies using a DHCP option
+code 51 this value is used if it is not lesser than the  minimum (in this case
+the minimum is returned) or greater than the maximum (in this case the
+maximum is used).</note>
+
+<note>Both <command>renew-timer</command>
+and <command>rebind-timer</command> are optional. The server will only
+send rebind-timer to the client, via DHCPv4 option code 59, if it is
+less than lease valid lifetime; and it will only send renew-timer, via
+DHCPv4 option code 58, if it is less than rebind-timer (or lease valid
+lifetime if rebind-timer was not specified). In their absence, the
+client should select values for T1 and T2 timers according
+to <link xmlns:xlink="http://www.w3.org/1999/xlink"
+xlink:href="http://tools.ietf.org/html/rfc2131">RFC 2131</link>. See
+section <xref linkend="dhcp4-t1-t2-times"/> for more details on
 generating T1 and T2.</note></para>
 
 <para>The <command>interfaces-config</command> map specifies the server

diff --git a/doc/guide/dhcp6-srv.xml b/doc/guide/dhcp6-srv.xml
index c9290b7bcab4b020a39a61458851bb78afb44186..b332b9a5ebc713ef1aa31129d31a268d04a65c0a 100644 (file)
--- a/doc/guide/dhcp6-srv.xml
+++ b/doc/guide/dhcp6-srv.xml
@@ -2046,6 +2046,7 @@ should include options from the new option space:
 
     <section xml:id="dhcp6-t1-t2-times">
       <title>Controlling the Values Sent for T1 and T2 Times</title>
+      <para>
       According to <link xmlns:xlink="http://www.w3.org/1999/xlink"
       xlink:href="http://tools.ietf.org/html/rfc8415">RFC 8415, section 21.4</link>,
       the recommended T1 and T2 values are 50% and 80%
@@ -2054,7 +2055,41 @@ should include options from the new option space:
       percentages of the preferred lease time.  The server's behavior is governed
       by combination of configuration parameters, two of which have already been
       mentioned.
-      <para>
+      </para><para>
+      From Kea 1.6.0 lease preferred and valid lifetime are extended from
+      single values to triplets with minimum, default and maximum values using:
+      <itemizedlist>
+        <listitem>
+         <simpara><command>min-preferred-lifetime</command> - specifies the minimal preferred lifetime (optional).
+          </simpara>
+        </listitem>
+        <listitem>
+         <simpara><command>preferred-lifetime</command> - specifies the default preferred lifetime.
+          </simpara>
+        </listitem>
+        <listitem>
+         <simpara><command>max-preferred-lifetime</command> - specifies the maximal preferred lifetime (optional).
+          </simpara>
+        </listitem>
+        <listitem>
+         <simpara><command>min-valid-lifetime</command> - specifies the minimal valid lifetime (optional).
+          </simpara>
+        </listitem>
+        <listitem>
+         <simpara><command>valid-lifetime</command> - specifies the default valid lifetime.
+          </simpara>
+        </listitem>
+        <listitem>
+         <simpara><command>max-valid-lifetime</command> - specifies the maximal valid lifetime (optional).
+          </simpara>
+        </listitem>
+      </itemizedlist>
+      When the client does not specify lifetimes the default is used. When
+      it specifies a lifetime using IAADDR or IAPREFIX sub option with not
+      zero values these values are used when they are between configured
+      minimal (lower values are round up) and maximal (larger values are
+      round down) bounds.
+      </para><para>
       To send specific, fixed values use the following two parameters:
       <itemizedlist>
         <listitem>