|OS type and version||CentOS Linux 7.9.2009|
Some time ago the “BIND DNS Server” did not start for me, I did not give it much importance since the websites worked correctly.
After stopping receiving emails sent from the server, I thought that this could be the problem as the BIND DNS was not set up and the SPF was not sent correctly.
I fixed this issue with this ticket:
I Remove the content of my parameters from my file, to leave it empty as indicated in the post
auto_chroot=sh -c '. /etc/sysconfig/named && echo "$ROOTDIR"' chroot=/var/named/chroot
I tried to run the BIND DNS and it worked correctly, it works again
But the emails still do not arrive, checking the postfix user mail I found the following errors:
This is the mail system at host xxxxxxx.localdomain. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to postmaster. If you do so, please include this problem report. You can delete your own text from the attached returned message. The mail system <email@example.com>: host gmail-smtp-in.l.google.com[xxx.xx.27.27] said: 550-5.7.26 This mail is unauthenticated, which poses a security risk to the 550-5.7.26 sender and Gmail users, and has been blocked. The sender must 550-5.7.26 authenticate with at least one of SPF or DKIM. For this message, 550-5.7.26 DKIM checks did not pass and SPF check for [ns3121678.localdomain] 550-5.7.26 did not pass with ip: [5.1xx.1xx0.67]. The sender should visit 550-5.7.26 https://support.google.com/mail/answer/81126#authentication for 550 5.7.26 instructions on setting up authentication. j25-20020aa7c0d9000000b0050bf9999de9si643513edp.620 - gsmtp (in reply to end of DATA command)
for google and for yahoo for example
This is the mail system at host xxxx.localdomain. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to postmaster. If you do so, please include this problem report. You can delete your own text from the attached returned message. The mail system <firstname.lastname@example.org>: host mx-eu.mail.am0.yahoodns.net[1xxx.125.72.73] said: 554 Message permanently deferred due to unresolvable RFC.5321 from domain; see https://postmaster.yahooinc.com/error-codes (in reply to end of DATA command)
I was checking the SPF and I think they are configured correctly:
xxxxxxxxxxxxxxx.es. IN MX 5 mail.xxxxxxxxxx.es. xxxxxxxxxxxxxxx.es. IN TXT "v=spf1 a mx a:xxxxxxxxxxxxx.es ip4:5.xxx.190.67 ip4:5.xxx.190.67 ip6:xxx:41d0:0008:c743::1 ?all"
Do you have any idea what could be happening?
Thank you very much!!!