<div dir="ltr">On 5 April 2013 22:30, SebA <span dir="ltr"><<a href="mailto:spah@syntec.co.uk" target="_blank">spah@syntec.co.uk</a>></span> wrote:<br><div class="gmail_extra"><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<div><span style="font-family:Arial">I wonder if it could
be related to the fact that DiG needs to be invoked with -x for PTR
checks.</span></div></div></blockquote><div><br></div><div style>Not required for PTR checks.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><div>
<span style="font-family:Arial"> A quick look at the DiG man page suggests you could use
either:</span><br></div>
<div><font face="Arial"><span># dig -t
PTR my.ip.ad.dr.ess</span></font></div>
<div><font face="Arial"><span>Or:</span></font></div>
<div><font face="Arial"><span>
<div><font face="Arial"><span># dig
my.ip.ad.dr.ess PTR</span></font></div></span></font></div></div></blockquote><div><br></div><div style>No, it's more like this:</div><div style><br></div><div style># dig ess.addr.ip.my.in-addr.arpa PTR</div><div style>
</div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>
<div><font face="Arial"><span>However, this is not
the case. A closer looks reveals you have to use:</span></font></div>
<div><font face="Arial"><span>
<div><font face="Arial"><span># dig -x
my.ip.ad.dr.ess</span></font></div></span></font></div></div></blockquote><div style><br></div><div style>The -x option is a convenience, and it means not only "set type to PTR" but also "reverse octets and append 'in-addr.arpa'".</div>
<div style><br></div><div style>I'm not in a position to check until tomorrow, but I'm confident that I successfully test for the localhost address like so<br><br></div><div style> DNS=PTR:1.0.0.127.in-addr.arpa</div>
<div style><br></div><div style>J</div><div style><br></div></div></div></div>