[qmailtoaster] Re: Reverse DNS does not match SMTP Banner
Amit is correct. It might effect spam scoring (I don't know that it does), but it should not prevent acceptance by the destination server. Here's what RFC 2821 says about this: An SMTP server MAY verify that the domain name parameter in the EHLO command actually corresponds to the IP address of the client. However, the server MUST NOT refuse to accept a message for this reason if the verification fails: the information about verification failure is for logging and tracing only. -- -Eric 'shubes' On 10/20/2010 11:13 AM, Amit Dalia wrote: Hi Christian, Please find mxtoolbox output below: 220 relay.that-aviation.com - Welcome SMTP Server ESMTP Not an open relay. 0 seconds - Good on Connection time 2.153 seconds - Good on Transaction time OK - 151.1.205.164 resolves to relay.that-aviation.com OK - Reverse DNS matches SMTP Banner Even if RDNS doesn't match with SMTP banner as far as I know it won't affect your mailing. Regards, Amit At Wednesday, 20-10-2010 on 23:22 Christian Ferrati wrote: Hi, I have a problem with my smtp server If I test my server with mxtoolbox.com, receive this warning message: “Reverse DNS does not match SMTP Banner”. http://www.mxtoolbox.com/public/images/btn_green.gifNot an open relay. http://www.mxtoolbox.com/public/images/btn_green.gif 0 seconds - Good on Connection time http://www.mxtoolbox.com/public/images/btn_green.gif 2.122 seconds - Good on Transaction time http://www.mxtoolbox.com/public/images/btn_green.gif OK - 151.1.205.164 resolves to relay.that-aviation.com http://www.mxtoolbox.com/public/images/btn_yellow.gif Warning - Reverse DNS does not match SMTP Banner My server hostname is: relay.that-aviation.com and with dig tools, all answer section are correct: 164.205.1.151.in-addr.arpa. 14400 IN PTR relay.that-aviation.com. that-aviation.com. 86400 IN MX 10 relay.that-aviation.com. Ho I can fix the problem? With this problem I have problems to send e-mails with some provider or client? Thank you very much Christian Ferrati Dipartimento Tecnico/Sistemi Smartcom SpA Via R. Lepetit, 8 – 20020 Lainate (MI) Tel. 0299813311 Fax 0299813197 www.smart-com.it http://www.smart-com.it / / *Copia di Smart_firma * * * *Rispetta l'ambiente. Non stampare questa mail se non è necessario.* *Respect the environment. Please print this email, only if strictly necessary.* * * *cid:image001.jpg@01CAC46F.6AE5A7D0* Privacy, D. Lgs. n. 196/2003 n. 196, si precisa che le informazioni contenute in questo messaggio sono riservate e ad uso esclusivo del destinatario. Qualora il messaggio in parola Vi fosse pervenuto per errore, Vi invitiamo ad eliminarlo senza copiarlo e a non inoltrarlo a terzi, dandocene gentilmente comunicazione ai recapiti in calce. I Vostri dati personali, le Vostre coordinate di posta elettronica da Voi fornitici saranno utilizzati per i necessari adempimenti istituzionali e/o per obblighi di legge e non saranno oggetto di comunicazione o diffusione a terzi e saranno trattati sia in forma elettronica, che cartacea. Ricordiamo infine che Vi sono riconosciuti i diritti di cui all'art. 7 del D. Lgs. 196/03 ( tra cui diritto di rettifica, aggiornamento, cancellazione). Per comunicazioni tel. 0299813311– fax. 0299813197 oppure inviate una e-mail a priv...@smart-com.it mailto:priv...@smart-com.it - Qmailtoaster is sponsored by Vickers Consulting Group (www.vickersconsulting.com) Vickers Consulting Group offers Qmailtoaster support and installations. If you need professional help with your setup, contact them today! - Please visit qmailtoaster.com for the latest news, updates, and packages. To unsubscribe, e-mail: qmailtoaster-list-unsubscr...@qmailtoaster.com For additional commands, e-mail: qmailtoaster-list-h...@qmailtoaster.com
Re: [qmailtoaster] Re: Reverse DNS does not match SMTP Banner
Hi folks, Is this the same issue you are discussing please? Remote host said: 554 This server requires PTR for unauthenticated connections. On 21/10/2010 7:11 AM, Eric Shubert wrote: Amit is correct. It might effect spam scoring (I don't know that it does), but it should not prevent acceptance by the destination server. Here's what RFC 2821 says about this: An SMTP server MAY verify that the domain name parameter in the EHLO command actually corresponds to the IP address of the client. However, the server MUST NOT refuse to accept a message for this reason if the verification fails: the information about verification failure is for logging and tracing only. -- best wishes Tony White - Qmailtoaster is sponsored by Vickers Consulting Group (www.vickersconsulting.com) Vickers Consulting Group offers Qmailtoaster support and installations. If you need professional help with your setup, contact them today! - Please visit qmailtoaster.com for the latest news, updates, and packages. To unsubscribe, e-mail: qmailtoaster-list-unsubscr...@qmailtoaster.com For additional commands, e-mail: qmailtoaster-list-h...@qmailtoaster.com
[qmailtoaster] Re: Reverse DNS does not match SMTP Banner
No, but it's related. Your sever's IP address must have an rDNS entry (maintained by your ISP) in order for most servers to receive mail from you. The rDNS entry should also be resolvable. What we're saying here, however, is that the rDNS name does not need to match the name provided in the EHLO greeting (smtpgreeting file). BL, the 554 error you have indicates that there is no rDNS for your server's IP address, or perhaps if there is an rDNS that it's not resolvable. The 'host' command is handy for checking this. $ host qmailtoaster.com qmailtoaster.com has address 66.226.75.14 qmailtoaster.com mail is handled by 10 mail.qmailtoaster.com. $ host mail.qmailtoaster.com mail.qmailtoaster.com has address 70.60.227.157 $ host 70.60.227.157 157.227.60.70.in-addr.arpa domain name pointer mail.qmailtoaster.com. $ In this case, you see that the pointer (last line) is mail.qmailtoaster.com. This is good and clear, but not necessary. It could resolve to somehost.somedomain.com and things would still work, just so long as somehost.somedomain.com resolved to an IP address. It wouldn't necessarily need to resolve to your server's address, but it's nice when it does. -- -Eric 'shubes' On 10/20/2010 04:18 PM, Tony White wrote: Hi folks, Is this the same issue you are discussing please? Remote host said: 554 This server requires PTR for unauthenticated connections. On 21/10/2010 7:11 AM, Eric Shubert wrote: Amit is correct. It might effect spam scoring (I don't know that it does), but it should not prevent acceptance by the destination server. Here's what RFC 2821 says about this: An SMTP server MAY verify that the domain name parameter in the EHLO command actually corresponds to the IP address of the client. However, the server MUST NOT refuse to accept a message for this reason if the verification fails: the information about verification failure is for logging and tracing only. - Qmailtoaster is sponsored by Vickers Consulting Group (www.vickersconsulting.com) Vickers Consulting Group offers Qmailtoaster support and installations. If you need professional help with your setup, contact them today! - Please visit qmailtoaster.com for the latest news, updates, and packages. To unsubscribe, e-mail: qmailtoaster-list-unsubscr...@qmailtoaster.com For additional commands, e-mail: qmailtoaster-list-h...@qmailtoaster.com
[qmailtoaster] Re: Reverse DNS does not match SMTP Banner
On 10/20/2010 06:35 PM, Tony White wrote: Hi Eric, Thanks for the answer! I assume then that an A record is not sufficient for this response? The server had an A record but no PTR. I would have thought an A record would suffice? An A record is enough to find the server, but checking the rDNS (PTR) record for the address is an anti-spam measure. spamdyke does this, in addition to several other tests. Should I ask the sysadmin why they chose to recognise only PTR records? No, you should ask your ISP to create an rDNS record for the IP address that your QMT host is on. -- -Eric 'shubes' On 21/10/2010 11:19 AM, Eric Shubert wrote: No, but it's related. Your sever's IP address must have an rDNS entry (maintained by your ISP) in order for most servers to receive mail from you. The rDNS entry should also be resolvable. What we're saying here, however, is that the rDNS name does not need to match the name provided in the EHLO greeting (smtpgreeting file). BL, the 554 error you have indicates that there is no rDNS for your server's IP address, or perhaps if there is an rDNS that it's not resolvable. The 'host' command is handy for checking this. $ host qmailtoaster.com qmailtoaster.com has address 66.226.75.14 qmailtoaster.com mail is handled by 10 mail.qmailtoaster.com. $ host mail.qmailtoaster.com mail.qmailtoaster.com has address 70.60.227.157 $ host 70.60.227.157 157.227.60.70.in-addr.arpa domain name pointer mail.qmailtoaster.com. $ In this case, you see that the pointer (last line) is mail.qmailtoaster.com. This is good and clear, but not necessary. It could resolve to somehost.somedomain.com and things would still work, just so long as somehost.somedomain.com resolved to an IP address. It wouldn't necessarily need to resolve to your server's address, but it's nice when it does. - Qmailtoaster is sponsored by Vickers Consulting Group (www.vickersconsulting.com) Vickers Consulting Group offers Qmailtoaster support and installations. If you need professional help with your setup, contact them today! - Please visit qmailtoaster.com for the latest news, updates, and packages. To unsubscribe, e-mail: qmailtoaster-list-unsubscr...@qmailtoaster.com For additional commands, e-mail: qmailtoaster-list-h...@qmailtoaster.com
