<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body text="#000000" bgcolor="#FFFFFF">
    <tt>If you're clients are roaming between networks and are not
      releasing leases you may wish to use this flag:<br>
      <br>
      <br>
    </tt>
    <p style="margin-left:14%; margin-top: 1em">The
      <i>one-lease-per-client</i> statement</p>
    <p style="margin-left:18%; margin-top: 1em"><b>one-lease-per-client</b>
      <i>flag</i><b>;</b></p>
    <p style="margin-left:18%; margin-top: 1em">If this flag is
      enabled, whenever a client sends a DHCPREQUEST for a
      particular lease, the server will automatically free any
      other leases the client holds. This presumes that when the
      client sends a DHCPREQUEST, it has forgotten any lease not
      mentioned in the DHCPREQUEST - i.e., the client has only a
      single network interface <i>and</i> it does not remember
      leases it’s holding on networks to which it is not
      currently attached. Neither of these assumptions are
      guaranteed or provable, so we urge caution in the use of
      this statement.</p>
    <p style="margin-left:18%; margin-top: 1em"><br>
    </p>
    <p style="margin-left:18%; margin-top: 1em"><br>
    </p>
    <div class="moz-cite-prefix">On 9/6/19 11:47 PM, Surya Teja wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CA+0Ac3yLX_L3VUo03hnoKijfyZrzhGbPcBjiGqJH6nYuBSPuFQ@mail.gmail.com">
      <meta http-equiv="content-type" content="text/html; charset=UTF-8">
      <div dir="auto">Hi Bill,
        <div dir="auto"><br>
        </div>
        <div dir="auto">Thanks for reply as suggested i have increased
          lease time to one hour and I observerd one more scenario when
          the client moves from one subnet to another subnet ( lease
          time say 1hr). The client got IP from the second subnet scope
          but the previous IP in the 1st subnet is still in hold and in
          the lease file. It still recorded an active entry. How can the
          dhcp server reclaims those unused IP's? Do we have any
          configuration statement making dhcp to cross check all the
          active IP's of that scope before saying no free leases.</div>
        <div dir="auto">The first IP is getting into free state after
          completing its 1 hour lease duration till that time it is
          active mode only.</div>
        <div dir="auto"><br>
        </div>
        <div dir="auto">Thanks in advance.</div>
      </div>
      <br>
      <div class="gmail_quote">
        <div dir="ltr" class="gmail_attr">On Sat, 7 Sep 2019, 00:33 Bill
          Shirley, <<a href="mailto:bill@c3po.polymerindustries.biz"
            moz-do-not-send="true">bill@c3po.polymerindustries.biz</a>>
          wrote:<br>
        </div>
        <blockquote class="gmail_quote" style="margin:0 0 0
          .8ex;border-left:1px #ccc solid;padding-left:1ex">
          <div text="#000000" bgcolor="#FFFFFF"> Note: two minutes (120
            seconds) is a very short lease time.<br>
            <br>
            Are you sure you're looking at the correct lease file?  Your
            grep says you have <b>no</b><b><br>
            </b><b>leases</b> on 192.168.3.x.<br>
            <br>
            Your log entries via looks strange.  I would think it should
            contain the interface name:<br>
            <font color="#993300"><tt>DHCPDISCOVER from
                40:4e:36:d2:bf:9d via wifi<br>
                DHCPDISCOVER from b4:18:d1:69:02:f9 (Bobs-iPhone) via
                wifi</tt><tt><br>
              </tt></font><br>
            Bill<br>
            <br>
            <div class="m_8537218324372512450moz-cite-prefix">On
              9/6/2019 6:25 AM, Surya Teja wrote:<br>
            </div>
            <blockquote type="cite">
              <div dir="ltr">Hi 
                <div>I have configured the dhcp on my local environment 
                  with the configuration as </div>
                <div>=================================</div>
                <div>subnet 192.168.3.0 netmask 255.255.255.0 {<br>
                          pool {<br>
                                  range 192.168.3.3 192.168.3.143;<br>
                          }<br>
                                  default-lease-time 120;<br>
                                  max-lease-time 120;<br>
                                  option domain-name "<a
                    href="http://example.com" target="_blank"
                    rel="noreferrer" moz-do-not-send="true">example.com</a>";<br>
                                  option routers 192.168.3.1;<br>
                                  option subnet-mask 255.255.255.0;<br>
                          }<br>
                </div>
                <div>But no client is able to get the IP and in the logs
                  I can see:<br>
                  DHCPDISCOVER from 84:EF:18:6A:89:DE via <a
                    href="http://192.168.3.11" target="_blank"
                    rel="noreferrer" moz-do-not-send="true">192.168.3.11</a>:
                  network <a href="http://192.168.3.0/24"
                    target="_blank" rel="noreferrer"
                    moz-do-not-send="true">192.168.3.0/24</a>:<b> no
                    free leases</b><br>
                  DHCPDISCOVER from 00:FF:4A:81:D5:A5 via <a
                    href="http://192.168.3.16" target="_blank"
                    rel="noreferrer" moz-do-not-send="true">192.168.3.16</a>:
                  network <a href="http://192.168.3.0/24"
                    target="_blank" rel="noreferrer"
                    moz-do-not-send="true">192.168.3.0/24</a>: <b>no
                    free leases</b><br>
                </div>
                <div>But it is not possible and none of the client get
                  the lease from the specified network. I cross checked
                  in the lease file also </div>
                <div>[root@dhcpserver]# cat dhcpd.leases | grep
                  192.168.3 -A 10 -B 10<br>
                  [root@dhcpserver]#<br>
                </div>
                <div>It doesn't shows any entry <br>
                  <br>
                </div>
                <div>Any help is appreciated thanks in advance  <br>
                </div>
              </div>
              <br>
              <fieldset
                class="m_8537218324372512450mimeAttachmentHeader"></fieldset>
              <pre class="m_8537218324372512450moz-quote-pre">_______________________________________________
dhcp-users mailing list
<a class="m_8537218324372512450moz-txt-link-abbreviated" href="mailto:dhcp-users@lists.isc.org" target="_blank" rel="noreferrer" moz-do-not-send="true">dhcp-users@lists.isc.org</a>
<a class="m_8537218324372512450moz-txt-link-freetext" href="https://lists.isc.org/mailman/listinfo/dhcp-users" target="_blank" rel="noreferrer" moz-do-not-send="true">https://lists.isc.org/mailman/listinfo/dhcp-users</a>
</pre>
            </blockquote>
          </div>
          _______________________________________________<br>
          dhcp-users mailing list<br>
          <a href="mailto:dhcp-users@lists.isc.org" target="_blank"
            rel="noreferrer" moz-do-not-send="true">dhcp-users@lists.isc.org</a><br>
          <a href="https://lists.isc.org/mailman/listinfo/dhcp-users"
            rel="noreferrer noreferrer" target="_blank"
            moz-do-not-send="true">https://lists.isc.org/mailman/listinfo/dhcp-users</a><br>
        </blockquote>
      </div>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <pre class="moz-quote-pre" wrap="">_______________________________________________
dhcp-users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:dhcp-users@lists.isc.org">dhcp-users@lists.isc.org</a>
<a class="moz-txt-link-freetext" href="https://lists.isc.org/mailman/listinfo/dhcp-users">https://lists.isc.org/mailman/listinfo/dhcp-users</a>
</pre>
    </blockquote>
    <br>
  </body>
</html>