Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!


Gmail is rejection emails from mail server
New on LowEndTalk? Please Register and read our Community Rules.

All new Registrations are manually reviewed and approved, so a short delay after registration may occur before your account becomes active.

Gmail is rejection emails from mail server

ahmiqahmiq Member
edited January 2014 in Help

Hi ,
recently gmail delivery is not possible from my vps server. This was a backup server and was not used much. It has ipv6 on it. The ipv4 is not in any blacklist.
When sending email to gmail i get a reply:
SMTP error from remote mail server after end of data: host aspmx.l.google.com [2a00:1450:400c:c05::1a]: 550-5.7.1 [2a00:d880:3:1::d2de:3f34 1] Our system has detected an unusual 550-5.7.1 rate of unsolicited mail originating from your IP address. To protect 550-5.7.1 our users from spam, mail sent from your IP address has been blocked. 550-5.7.1 Please visit http://www.google.com/mail/help/bulk_mail.html to review 550 5.7.1 our Bulk Email Senders Guidelines. h15si5313771wic.51 - gsmtp

is it possible to only use ipv4 for mail delivery? should i ask the provider to remove ipv6 from my vps.?
i am running centos 6.5

Comments

  • What's your MTA? With Postfix, it's quite easy by adding inet_protocols = ipv4 to main.cf.

  • @Chumbi said:
    What's your MTA? With Postfix, it's quite easy by adding inet_protocols = ipv4 to main.cf.

    Hi sorry , i dont have much knowledge about it , i am using vesta cP , with exim and dovecot.

  • perennateperennate Member, Host Rep

    Also make sure your configuration is set to prevent sending of mail from unauthorized servers.

  • @perennate said:
    Also make sure your configuration is set to prevent sending of mail from unauthorized servers.

    yep it doesnt allow unauthorized emails , but how do i put it to send mails via ipv4 only.

  • before:
    ]# lsof -Pni | grep exim exim 2441 exim 3u IPv6 625492738 0t0 TCP *:25 (LISTEN) exim 2441 exim 4u IPv4 625492739 0t0 TCP *:25 (LISTEN) exim 2441 exim 5u IPv6 625492740 0t0 TCP *:465 (LISTEN) exim 2441 exim 6u IPv4 625492741 0t0 TCP *:465 (LISTEN) exim 2441 exim 7u IPv6 625492742 0t0 TCP *:587 (LISTEN) exim 2441 exim 8u IPv4 625492743 0t0 TCP *:587 (LISTEN) exim 2441 exim 9u IPv6 625492744 0t0 TCP *:2525 (LISTEN) exim 2441 exim 10u IPv4 625492745 0t0 TCP *:2525 (LISTEN)

    okay found it. by locating the exim.conf

    adding:
    disable_ipv6 = true

    service exim restart

    # lsof -Pni | grep exim exim 13134 exim 3u IPv4 633818603 0t0 TCP *:25 (LISTEN) exim 13134 exim 4u IPv4 633818604 0t0 TCP *:465 (LISTEN) exim 13134 exim 5u IPv4 633818605 0t0 TCP *:587 (LISTEN) exim 13134 exim 6u IPv4 633818606 0t0 TCP *:2525 (LISTEN)

  • What's the long-term fix for this? Switching to IPv4 is just buying you time until you're blacklisted again. I've seen this message before, but haven't looked into it much. If you find a durable solution, it'd be great if you filled us in.

  • mikhomikho Member, Host Rep

    Fix your rDNS is one thing

  • PTR+DKIM+Clean IP = Profit

  • @blergh_ said:
    PTR+DKIM+Clean IP = Profit

    Does SPF apply as well, or is DKIM +PTR all that is needed? I've done all three and I'm fine.

  • said: Hi , recently gmail delivery is not possible from my vps server. This was a backup server and was not used much.

    Your mail server might be exploited to send spam in bulk. You should check mail server log. I assume you do not send any bulk mail from a backup server.

  • I also faced the same problem before: http://lowendtalk.com/discussion/18678/help-plz-how-to-prevent-ipv6-addresses-from-sending-spam. I don't think this has anything to do with sending actual spam. I think the problem is due to Google's strict mail policy for IPv6 and your IPv6 address failing to meet their IPv6 guidelines. http://lmgtfy.com/?q=google+mail+ipv6

    The explanation is right there in the link in your error message: https://support.google.com/mail/answer/81126

    Additional guidelines for IPv6:

    • The sending IP must have a PTR record (i.e., a reverse DNS of the sending IP) and it should match the IP obtained via the forward DNS resolution of the hostname specified in the PTR record. Otherwise, mail will be marked as spam or possibly rejected.
    • The sending domain should pass either SPF check or DKIM check. Otherwise, mail might be marked as spam.

    You have 3 options:

    1. Setup your IPv6 with valid rdns, SPF and DKIM.

    2. Configure your MTA to prefer IPv4 over IPv6 or

    3. Disable your IPv6 if you don't use them.

  • ahmiqahmiq Member
    edited January 2014

    @amhoab FYI,
    @atomic7 is right , there was no spam activity , google was just too nosy. Here is what you can do to fix this problem.

    1) In your bind create a AAA record for domain/sub you are trying to send mail with
    2) put the same rDNS for your ipv6 (my host allows setting it by itself from solus)
    3) dkim and spf records for your domain

    and thats it , google will accept your emails now , without any problem.

  • Got a quick question about mail servers, didn't think it was worth starting a new thread:

    • Mail server runs on vps1.example.net
    • www.example.net & example.net run on vps1.example.net
    • MX record for example.net = vps1.example.net
    • Mail account sending e-mail from this box is [email protected]

    Now, vps1.example.net's IP would need the rDNS 'vps1.example.net', right?

    But if I were to have the MX record pointing to mail.example.net, which has the same IP as vps1, the IP would need the rDNS mail.example.net, no?

  • @Melon said:

    I'm not sure if I clearly understand what you want to do but to be simple, and if I correctly remember, you can set more than one rDNS record for your IP.

Sign In or Register to comment.