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    Do you really need the <font color="#993300">allow unknown-clients</font>
    in your pool definition?<br>
    If you define any device with a <font color="#993300">host</font>
    statement then it won't be eligible<br>
    for the only pool in the 172.210.140.0 subnet.<br>
    <br>
    As I understand it, DHCP will use all the available leases before it
    will<br>
    recycle any for a DHCPDISCOVER.<br>
    <br>
    How does your DHCP know which subnet to use for a request?  Do you<br>
    have <font color="#993300">host</font> or <font color="#993300">class</font>
    statements?<br>
    <br>
    Bill<br>
    <br>
    <br>
    <div class="moz-cite-prefix">On 11/15/2017 9:49 AM, project722
      wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CAPBQMZCP+T+oYQBUfxZ2TJirTVyNXJUTnWPkWyA-u-6W9YyTNA@mail.gmail.com">
      <div dir="ltr">
        <div>shared-network "temp" {</div>
        <div>        subnet 172.210.140.0 netmask 255.255.252.0 {</div>
        <div>                option domain-name "<a
            href="http://example.net" moz-do-not-send="true">example.net</a>";</div>
        <div>                option routers 172.210.140.1;</div>
        <div>                ## Define the DHCP pool and access list for
          this pool.</div>
        <div>                pool {</div>
        <div>                        allow unknown-clients;</div>
        <div>                        failover peer "dhcp-failover";</div>
        <div>                        range 172.210.140.2
          172.210.140.255;</div>
        <div>                        range 172.210.141.1
          172.210.141.255;</div>
        <div>                        range 172.210.142.1
          172.210.142.255;</div>
        <div>                        range 172.210.143.1
          172.210.143.254;</div>
        <div>                        </div>
        <div>                }</div>
        <div>        }</div>
        <div>        subnet 172.210.144.0 netmask 255.255.252.0 {</div>
        <div>                option routers 172.210.144.1;</div>
        <div>                </div>
        <div>        }</div>
        <div> }        </div>
        <div><br>
        </div>
        <div>I can't post log entries as we have expanded the pool to
          patch the issue, so currently there are no errors. However,
          this pool only shows 74% utilization. And all it takes is a
          few more turn-ups to cause this problem.      </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div>      Subnet <a href="http://172.210.140.0/22"
            moz-do-not-send="true">172.210.140.0/22</a></div>
        <div>--------------------------------------------------</div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div>     Monitoring:      ON</div>
        <div>     Warning limit:   80%</div>
        <div>     Critical limit:  90%</div>
        <div>     Active leases:   762/1018 (74.9%)</div>
        <div><br>
        </div>
        <div>As I've mentioned before, the only thing that stands out to
          me in dhcpd.leases is the fact that we have a couple hundred
          of "expired" leases, which could and should be used, even
          though these are actually being held in the expectation that
          the previous client will return. (At least, that is my
          understanding) </div>
        <div><br>
        </div>
        <div>But, what is expected behavior here? For example, if we
          have 500 leases, 250 of them have a binding state of active
          and the other 250 have expired if a new client comes along
          DHCP should free up one of the expired ones, correct?</div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div>    </div>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">On Tue, Nov 14, 2017 at 3:24 PM, Bill
          Shirley <span dir="ltr"><<a
              href="mailto:bill@c3po.polymerindustries.biz"
              target="_blank" moz-do-not-send="true">bill@c3po.polymerindustries.biz</a>></span>
          wrote:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0
            .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div text="#000000" bgcolor="#FFFFFF"> Post your pool
              definition and log file excerpts.<span class="HOEnZb"><font
                  color="#888888"><br>
                  <br>
                  Bill</font></span>
              <div>
                <div class="h5"><br>
                  <br>
                  <div class="m_86255357782825452moz-cite-prefix">On
                    11/14/2017 12:07 PM, project722 wrote:<br>
                  </div>
                </div>
              </div>
              <blockquote type="cite">
                <div>
                  <div class="h5">
                    <div dir="ltr">
                      <div>
                        <div>
                          <div>We had an unusual problem last night
                            where the server was not able to give out
                            any more leases from a specific pool. The
                            server logs showed " no more free leases".
                            This is a RHEL 6.7 server running dhcp
                            4.1.1. <br>
                            <br>
                          </div>
                          We have scripts that run which look for active
                          leases. In the pool in question we had over
                          200 available leases but the server was unable
                          to provide them to a client. I dug around in
                          dhcpd.leases and found what I think is the
                          problem. I found a ton of leases in the
                          "expired" state with an end date of 11/6.
                          Which, If I am correct, will never move into
                          it next binding state of free so it can be
                          used because its a date in the past.  <br>
                          <br>
                        </div>
                        Here is an example of one:<br>
                        <br>
                        lease 172.210.141.159 {<br>
                          starts 2 2017/11/07 11:40:37;<br>
                          ends 2 2017/11/07 12:10:37;<br>
                          tstp 2 2017/11/14 11:55:37;<br>
                          cltt 2 2017/11/07 11:40:37;<br>
                          binding state expired;<br>
                          next binding state free;<br>
                        <br>
                      </div>
                      Am I correct here? If so, what causes this problem
                      and how can I fix it? I have restarted dhcpd, but
                      that does not help. If I were to edit
                      /var/lib/dhcp/dhcpd.leases manually and remove
                      these entries what are some things I should take
                      into consideration?<br>
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              <br>
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