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<P><FONT SIZE=2>Every now and then we get a bounce on emails that are sent through one of our mails servers located on 64.187.3.170. The bounce messages look as follows and appear to indicate that our reverse zone is missing a record, though the record is there and resolves through nslookup. The ISP delegates a number of IP addresses from the zone back to us (16 IP addresses). So my guess is that our zone file needs to be rewritten or there may be something else I'm missing.<BR>
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<first_last@some_domain.com>: host mx.some_domain.com[xxx.xx.xx.xx] said: 450 4.7.1 Client<BR>
host rejected: cannot find your hostname, [64.187.3.170] (in reply to RCPT<BR>
TO command)<BR>
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Performing a manual reverse lookup correctly displays the correct name for 170.3.187.64.in-addr.arpa. Our zone file looks as follows (other records removed):<BR>
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$ORIGIN .<BR>
$TTL 86400 ; 1 day<BR>
3.187.64.in-addr.arpa IN SOA ns1.blue-dot.ca. dnsadmin.ns1.blue-dot.ca. (<BR>
2009011401 ; serial<BR>
1800 ; refresh (30 minutes)<BR>
900 ; retry (15 minutes)<BR>
604800 ; expire (1 week)<BR>
1800 ; minimum (30 minutes)<BR>
)<BR>
NS ns1.blue-dot.ca.<BR>
NS ns2.blue-dot.ca.<BR>
NS ns3.blue-dot.ca.<BR>
$ORIGIN 3.187.64.in-addr.arpa.<BR>
170 PTR smtp3.netcraftcommunications.com.<BR>
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