I apologize if I re-post this message. But I had problems with the mail server and I'm not sure that it was posted. Hi, I have this zone: uniplan.it $ORIGIN . $TTL 3600 ; 1 hour uniplan.it IN SOA uniserv.uniplan.it. admin.uniplan.it. ( 2011101402 3600 1800 1209600 86400 ) $TTL 86400 ; 1 day NS uniserv.uniplan.it. NS uniserv1.uniplan.it. NS webserver.uniplan.it. $TTL 3600 ; 1 hour A 217.20.0.2 MX 10 uniserv.uniplan.it. $ORIGIN uniplan.it. axis2100 A 217.20.0.15 board A 217.20.0.140 clessidra A 217.20.0.32 $ORIGIN clessidra.uniplan.it. www A 217.20.0.32 $ORIGIN uniplan.it. frattamaggiore A 85.44.177.45 $ORIGIN frattamaggiore.uniplan.it. www A 85.44.177.45 $ORIGIN uniplan.it. ftp CNAME uniserv gargano A 217.20.0.73 $ORIGIN gargano.uniplan.it. www A 217.20.0.73 $ORIGIN uniplan.it. gesema.uniplan.it. IN A 85.33.176.119 $ORIGIN gesema.uniplan.it. <http://www.gesema.uniplan.it> www.gesema.uniplan.it. IN A 85.33.176.119 $ORIGIN uniplan.it. <http://www.gesemaeco> www.gesemaeco A 85.18.249.93 gm A 172.16.1.246 gm1mex A 172.16.80.61 gm2mex A 172.16.1.222 gm3mex A 172.16.1.222 localhost A 127.0.0.1 mailserver A 217.20.0.31 $ORIGIN mailserver.uniplan.it. mailserver A 217.20.0.31 $TTL 86400 ; 1 day $ORIGIN uniplan.it. $TTL 3600 ; 1 hour nt01 A 217.20.0.179 nt02 A 217.20.3.20 nt03 A 217.20.1.150 $TTL 86400 ; 1 day ovi A 217.20.0.31 $TTL 3600 ; 1 hour pomilia A 151.58.32.85 $ORIGIN pomilia.uniplan.it. www A 151.58.32.85 $ORIGIN uniplan.it. posta A 217.20.1.150 $ORIGIN posta.uniplan.it. www A 217.20.1.150 $ORIGIN uniplan.it. postfix A 217.20.0.76 radio A 217.20.0.73 $ORIGIN radio.uniplan.it. www A 217.20.0.73 $ORIGIN uniplan.it. rcis-01 A 217.20.0.1 rcis-02 A 217.20.0.14 rliv01-02 A 217.20.0.10 rliv02-02 A 217.20.0.13 rliv03-02 A 217.20.0.12 rliv04-02 A 217.20.0.11 sanmarcocavoti A 172.16.40.206 $ORIGIN sanmarcocavoti.uniplan.it. www A 172.16.40.206 $ORIGIN uniplan.it. spin0 A 217.20.1.8 spin1 A 217.20.3.3 spin2 A 217.20.3.2 spin3 A 217.20.3.103 www.radio.tanagro A 85.44.172.158 $TTL 14400 ; 4 hours uniplan TXT "v=spf1 a mx -all" $TTL 3600 ; 1 hour uniserv.uniplan.it. IN A 217.20.0.2 uniserv1.uniplan.it. IN A 217.20.0.3 watch02 A 217.20.0.176 watch03 A 217.20.0.177 weblinux A 217.20.0.72 webserver.uniplan.it. IN A 217.20.0.30 www CNAME uniserv www4 A 217.20.0.73 gol.uniplan.it. IN A 217.20.1.150 mailserver-dns.uniplan.it. IN A 217.20.0.2 uniserv.uniplan.it. PTR 217.20.0.2 uniserv1.uniplan.it. PTR 217.20.0.3 webserver.uniplan.it. PTR 217.20.0.30 I have created this reverse zone: 217.20.0. $ttl 38400 @ IN SOA uniserv.uniplan.it. system.uniplan.it. ( 2011101403 10800 3600 604800 38400 ) 2 IN NS uniserv.uniplan.it. 3 IN NS uniserv.uniplan.it. 30 IN NS uniserv.uniplan.it. 2 IN PTR uniserv.uniplan.it. 3 IN PTR uniserv1.uniplan.it. 30 IN PTR webserver.uniplan.it. I have tested the zone with RIPE Zone Delegation Checker and I have this error:

Check uniserv.uniplan.it details

PROBLEM_NO_REVERSE_MAPPING for entity uniserv.uniplan.it >Args: 217.20.0.2, uniserv.uniplan.it >Check uniserv1.uniplan.it details PROBLEM_NO_REVERSE_MAPPING for entity uniserv1.uniplan.it >Args: 217.20.0.3, uniserv1.uniplan.it >Check webserver.uniplan.it details PROBLEM_NO_REVERSE_MAPPING for entity webserver.uniplan.it >Args: 217.20.0.30, webserver.uniplan.it Can you help me to solve this error? Thanks.