Avatar of Jay Pe
Jay Pe
 asked on

Emails are being rejected from one of the external domain

Since past few days, I am not able to send email to any person one specific domain, I would call it xyxyxyxy.org. I am not sure if some changes were done on our network side or recipient's side.
When I sent test email from my unix server, I can see below message on /var/log/maillog

Jan  3 14:36:37 mail-relay-server postfix/smtp[114581]: CA0BA102B6E4: to=brian.harp@xyxyxyxy.org, relay=smtp1.xyxyxyxy.org[]:25, delay=0.06, delays=0.01/0/0.05/0, dsn=4.0.0, status=deferred (host smtp1.xyxyxyxy.org[] refused to talk to me: 554 No SMTPd here   202201032236360132090;12)

Open in new window

And this test too

[root@mail-relay-server ~]# telnet smtp1.xyxyxyxy.org 25
Connected to smtp1.xyxyxyxy.org. Escape character is '^]'. 554 No SMTPd here   202201032250260132555;12 Connection closed by foreign host. [root@mail-relay-server ~]# telnet smtp2.xyxyxyxy.org 25 Trying Connected to smtp2.xyxyxyxy.org. Escape character is '^]'. 554 No SMTPd here   202201032250310278916;10 Connection closed by foreign host. [root@mail-relay-server ~]#

Open in new window

Does it mean that recipient's domain is rejecting our mail and I should follow with them or something could be on our network or our mail server? All other emails and external emails are going as it is.


Unix OS* Postfix

Avatar of undefined
Last Comment

8/22/2022 - Mon

It looks as though they aer using an SMTP proxy as the front end, but the server behind it is currently unavailable.

What is the domain, check the MX records.

nslookup -q=mx domainname.suffi

Have you considered calling them?
whois domainname.com and call the technical contact.
if you lookup the IP you can check the arin registration, and call their technical contact if it is affiliated with the organization versus an ISP.

The MX is helpful if there are two listings, it might be possible to try the other and see if you can establish an SMTP connection. if that works, you could setup a conditional forwarder for the domain to use the SMTP connection that works versus the one that does not.

Though, notifying them of the issue might be a straightforward thing to do.
"Hey, your mail servers are down, messages sent to your arganization are being rejected..."
Jay Pe

Okay, here is the domain and it is able to resolve
[root@mail-relay-server ~]# nslookup -q=mx portlandoregon.gov

Non-authoritative answer:
portlandoregon.gov      mail exchanger = 10 smtp2.portlandoregon.gov.
portlandoregon.gov      mail exchanger = 10 smtp1.portlandoregon.gov.

Authoritative answers can be found from:
portlandoregon.gov      nameserver = ns2.portlandoregon.gov.
portlandoregon.gov      nameserver = ns1.portlandoregon.gov.
smtp2.portlandoregon.gov        internet address =
smtp1.portlandoregon.gov        internet address =
ns1.portlandoregon.gov  internet address =
ns2.portlandoregon.gov  internet address =

[root@mail-relay-server ~]#

Open in new window

They are able to get email from everywhere else, but not from us. Though this statement is from the end user, not from technical team. Before approaching them, I want to ensure that nothing is wrong/broken on our side.

View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
See Pricing Options
Start Free Trial
Ask your own question & get feedback from real experts
Find out why thousands trust the EE community with their toughest problems.
Your help has saved me hundreds of hours of internet surfing.