<div dir="ltr">So Donno how but it's working now. <br>I've rebooted both systems, Something I hate to do to solve a problem as it usually only ever removes a symptom. However logs now show RR's being removed. I'm going to monitor the situation.<div>Simon thanks for the time. It's appreciated. First time ever having to mail out to the dhcpd community and have to say it's been very welcoming thank you.</div><div>Kind Regards</div><div>Mark</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Aug 17, 2016 at 2:02 PM, Mark Mc Nicholas <span dir="ltr"><<a href="mailto:markmcn@section9.ie" target="_blank">markmcn@section9.ie</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><div><div>Hi Simon,<br></div>Thanks for pointing that out,<br></div>That is an artifact of some late night troubleshooting :) <br></div>Kind Regards<span class="HOEnZb"><font color="#888888"><br></font></span></div><span class="HOEnZb"><font color="#888888">Mark<br></font></span></div><div class="gmail_extra"><div><div class="h5"><br><div class="gmail_quote">On Wed, Aug 17, 2016 at 1:54 PM, Simon Hobson <span dir="ltr"><<a href="mailto:dhcp1@thehobsons.co.uk" target="_blank">dhcp1@thehobsons.co.uk</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span>Mark Mc Nicholas <<a href="mailto:markmcn@section9.ie" target="_blank">markmcn@section9.ie</a>> wrote:<br>
<br>
</span><span>> Below are the config's of DHCPD & Bind,<br>
<br>
<br>
</span><div><div>> ====DHCPD Config====<br>
><br>
> ddns-updates on;<br>
> ddns-update-style interim;<br>
> update-static-leases on;<br>
> key sun-key { algorithm hmac-md5; secret "123456789";}<br>
> allow unknown-clients;<br>
> use-host-decl-names on;<br>
><br>
> zone i.home.ie.{<br>
> primary <a href="http://moto.i.home.ie" rel="noreferrer" target="_blank">moto.i.home.ie</a>;<br>
> key sun-key;<br>
> }<br>
><br>
> # Common to all subnets<br>
> option domain-name "<a href="http://home.ie" rel="noreferrer" target="_blank">home.ie</a>";<br>
> default-lease-time 1800;<br>
> max-lease-time 14400;<br>
> authoritative;<br>
> allow unknown-clients;<br>
><br>
> subnet 172.17.2.0 netmask 255.255.255.128 {<br>
> range 172.17.2.41 172.17.2.100;<br>
> default-lease-time 1800;<br>
> max-lease-time 14400;<br>
> authoritative;<br>
> option routers 172.17.2.1;<br>
> option domain-name-servers 172.17.2.4,192.168.252.1 ;<br>
> option domain-name "<a href="http://i.home.ie" rel="noreferrer" target="_blank">i.home.ie</a>";<br>
> option domain-search "<a href="http://i.home.ie" rel="noreferrer" target="_blank">i.home.ie</a>";<br>
> option ntp-servers 193.1.219.116,193.1.31.66;<br>
> ddns-domainname "<a href="http://i.home.ie" rel="noreferrer" target="_blank">i.home.ie</a>.";<br>
> ddns-rev-domainname "in-addr.arpa.";<br>
><br>
> host skynet09{<br>
> hardware ethernet AC:CF:23:8D:10:60;<br>
> fixed-address 172.17.2.39;<br>
> ddns-hostname "skynet009";<br>
> }<br>
> }<br>
<br>
</div></div>The first thing to note is that you have a host declaration within a subnet. Host declarations are always global in scope, but do have inheritance - this can cause some "interesting" effects if the client pops up on another subnet. So, while it's not directly relevant to the problem you are enquiring about - put your host declarations in the global scope and save yourself some pain later on ;-)<br>
<span><br>
<br>
<br>
> Bind Logs of an Update<br>
><br>
> named[1563]: client 172.17.2.4#28949: updating zone '<a href="http://i.home.ie/IN" rel="noreferrer" target="_blank">i.home.ie/IN</a>': update unsuccessful: <a href="http://skynet001.i.home.ie" rel="noreferrer" target="_blank">skynet001.i.home.ie</a>: 'name not in use' prerequisite not satisfied (YXDOMAIN)<br>
> named[1563]: client 172.17.2.4#28949: signer "sun-key" approved<br>
> named[1563]: client 172.17.2.4#28949: updating zone '<a href="http://i.home.ie/IN" rel="noreferrer" target="_blank">i.home.ie/IN</a>': deleting rrset at '<a href="http://skynet001.i.home.ie" rel="noreferrer" target="_blank">skynet001.i.home.ie</a>' A<br>
> named[1563]: client 172.17.2.4#28949: updating zone '<a href="http://i.home.ie/IN" rel="noreferrer" target="_blank">i.home.ie/IN</a>': adding an RR at '<a href="http://skynet001.i.home.ie" rel="noreferrer" target="_blank">skynet001.i.home.ie</a>' A<br>
> named[1563]: client 172.17.2.4#28949: signer "sun-key" approved<br>
><br>
> DHCP Logs for the same device<br>
> dhcpd[6271]: DHCPREQUEST for 172.17.2.31 from ac:cf:23:8d:77:56 via eth0<br>
> dhcpd[6271]: DHCPACK on 172.17.2.31 to ac:cf:23:8d:77:56 via eth0<br>
> dhcpd[6271]: Added new forward map from <a href="http://skynet001.i.home.ie" rel="noreferrer" target="_blank">skynet001.i.home.ie</a>. to 172.17.2.31<br>
> dhcpd[6271]: Added reverse map from 31.2.17.172.in-addr.arpa. to <a href="http://skynet001.i.home.ie" rel="noreferrer" target="_blank">skynet001.i.home.ie</a>.<br>
<br>
</span>OK, that's all normal.<br>
But, I see 172.17.2.31 is not in the range (172.17.2.41 to 172.17.2.100) defined for dynamic clients, so I'm guessing that you have trimmed out a host declaration for skynet001 ? If so, then the answer is simple - DNS entries for these hosts are not automatically removed, because there is no mechanism to do so.<br>
<br>
More detail on that.<br>
When a host gets a lease from a static address assignment in a host declaration, there is no lease created by the server to go with it. Because it's a static assignment, there's no need to track it, and so there's a shortcut where from the client PoV it gets a lease, but the server doesn't bother recording it.<br>
As there is no lease recorded by the server, there's nothing to expire, and so nothing to trigger removal of the corresponding DDNS entries.<br>
Also, without the "update-static-leases on;" statement, you also would not get DNS updates on "lease" issue.<br>
<br>
If you need DDNS updates to remove the entries, then you'll have to use "real" leases. You can get much the same effect by creating a "reserved" lease. You can do this (AIUI) on a running server via OMAPI, or after stopping the server you can do it by editing the leases file to add/edit a lease with the "Reserved" keyword.<br>
A reserved lease acts just like any other dynamic lease (gets issued, renewed, expires, etc) except that it will never be re-assigned to another client.<br>
<div><div><br>
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</div></div></blockquote></div><br><br clear="all"><br></div></div><span class="">-- <br><div data-smartmail="gmail_signature"><div dir="ltr"><span style="color:rgb(0,0,0);font-family:sans-serif;line-height:19.1875px">Begin at the beginning,and go on till you come to the end: then stop.</span></div></div>
</span></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><span style="color:rgb(0,0,0);font-family:sans-serif;line-height:19.1875px">Begin at the beginning,and go on till you come to the end: then stop.</span></div></div>
</div>