https://6to4.nro.net/ I'm trying to setup reverse DNS for a 6to4 address using the above web site. IPv4: 220.245.31.42 IPv4 (hex): dc.f5.1f.2a IPv6: 2002:dcf5:1f2a::/48 Reverse: a.2.f.1.5.f.c.d.2.0.0.2.ip6.arpa Above is the web site's details about my system. Before anyone mentions it I know it's common practice to obscure details of addresses before posting to lists, but I'm not publishing anything that couldn't be discovered by reading headers of mail sent out from my system. Name server 1: ns.sws.net.au.______ Error Either you have entered an invalid nameserver description or the nameserver you refer to has no zone for this reverse delegation. When I try to submit the form I get the above errors from all of my DNS servers. zone "a.2.f.1.5.f.c.d.2.0.0.2.ip6.arpa" { type master; file "/etc/bind/data/a.2.f.1.5.f.c.d.2.0.0.2.ip6.arpa"; allow-transfer { REDACTED }; }; Above is the named.conf.local configuration for BIND. $TTL 604800 @ IN SOA ns.sws.net.au. root.sws.net.au. ( 2016041204 ; Serial 3600 ; Refresh 60 ; Retry 604800 ; Expire 3600 ) ; Default TTL IN NS ns.sws.net.au. IN NS othello.dycom.com.au. IN NS xkcd.gw90.de. 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0 IN PTR smtp.sws.net.au. Above is the complete zone file for a.2.f.1.5.f.c.d.2.0.0.2.ip6.arpa. Can anyone see anything I've done wrong? -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/