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    <div class="moz-cite-prefix">There's no way within the DNS protocol
      itself to reach out and tell a nameserver to purge an entry in its
      cache that hasn't expired yet.<br>
      <br>
      There are "out of band" ways: e.g. restart, recycle, rndc
      commands, etc. All of those require admin access to the nameserver
      instances in question. But nothing within the DNS protocol itself
      allows one to do this.<br>
      <br>
      That's why everyone is saying you need to reduce the TTL value
      *before* you make a change, if you want that change to be visible
      quickly.<br>
      <br>
                                                                     
                                                                     
                                  - Kevin<br>
      <br>
      On 10/15/2013 10:53 AM, babu dheen wrote:<br>
    </div>
    <blockquote
      cite="mid:1381848793.10395.YahooMailNeo@web190804.mail.sg3.yahoo.com"
      type="cite">
      <div style="color:#000; background-color:#fff; font-family:times
        new roman, new york, times, serif;font-size:12pt">
        <div><span>Hi Matus,</span></div>
        <div><span></span> </div>
        <span>
          <div><em>"The standard way to handle this situation is, when
              you know you are going to<br clear="none">
              make a change, to lower TTL of a particular RR to a small
              value (e.g.  300)<br clear="none">
              and after change to restore the TTL to sane standard value
              (e.g.  43200)."</em></div>
          <div><em></em> </div>
          <div><em>I just need clarification on your above update.</em></div>
          <div><em></em> </div>
          <div><em> If I change the TTL value on the particular zone
              after modifying a  record in Redhat Linux BIND Caching DNS
              server, My Redhat bind Caching DNS server cache would be
              refreshed after 300 seconds but what if my backend
              windows  DNS server is still responding to  end user old
              record from  from its cache?</em></div>
          <div><em></em> </div>
          <div><em></em> </div>
          <div><em>So my backend windows DNS server can get the newly
              modified record from DNS only when its contacting Redhat
              DNS server for the newly added date once Windows DNS cache
              is refreshed?</em></div>
          <div><em></em> </div>
          <div><em>Regards</em></div>
          <div><em>Babu</em></div>
          <div><em></em> </div>
        </span>
        <div class="yahoo_quoted" style="display: block;"> <br>
          <br>
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            serif; font-size: 12pt;">
            <div style="font-family: times new roman, new york, times,
              serif; font-size: 12pt;">
              <div dir="ltr"> <font size="2" face="Arial"> On Tuesday,
                  15 October 2013 3:04 PM, Matus UHLAR - fantomas
                  <a class="moz-txt-link-rfc2396E" href="mailto:uhlar@fantomas.sk"><uhlar@fantomas.sk></a> wrote:<br>
                </font> </div>
              <div class="y_msg_container">On 15.10.13 19:38, babu dheen
                wrote:<br clear="none">
                > I am running BIND caching DNS server in Redhat
                Linux. This DNS server is<br clear="none">
                >used as name server for other DNS servers which are
                running in Windows<br clear="none">
                >2003.  Whenever I modify a existing record in BIND
                DNS caching server zone,<br clear="none">
                >its not immediately taking affect in my Windows DNS
                servers.  But if I<br clear="none">
                >clear the Windows DNS server DNS cache, its taking
                affect.<br clear="none">
                <br clear="none">
                > Is it possible to enforce/refresh cache of other
                DNS server through BIND<br clear="none">
                > DNS server once modification is done in zone file?<br
                  clear="none">
                <br clear="none">
                No. Only server admins can maintain caches.<br
                  clear="none">
                <br clear="none">
                Your job is to set TTL high enough not to cause you big
                load and not to time<br clear="none">
                out when your servers fail, but low enough to refresah
                when needed.<br clear="none">
                <br clear="none">
                The standard way to handle this situation is, when you
                know you are going to<br clear="none">
                make a change, to lower TTL of a particular RR to a
                small value (e.g.  300)<br clear="none">
                and after change to restore the TTL to sane standard
                value (e.g.  43200).<br clear="none">
                <br clear="none">
                You may ask for access to win2003 servers to manipulate
                their caches, or<br clear="none">
                configure your zone as slave on them and send notifies
                to them, so they<br clear="none">
                notice as soon as possible.<br clear="none">
                <br clear="none">
                -- <br clear="none">
                Matus UHLAR - fantomas, <a moz-do-not-send="true"
                  href="" shape="rect"
                  ymailto="mailto:uhlar@fantomas.sk">uhlar@fantomas.sk</a>
                ; <a moz-do-not-send="true" href="" target="_blank"
                  shape="rect">http://www.fantomas.sk/</a><br
                  clear="none">
                Warning: I wish NOT to receive e-mail advertising to
                this address.<br clear="none">
                Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek
                reklamnu postu.<br clear="none">
                2B|!2B, that's a question!
                <div class="yqt9641222591" id="yqtfd90835"><br
                    clear="none">
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