Anyone from Proof Point or Comcast on this list?
ops.lists at gmail.com
Mon Apr 19 17:01:57 UTC 2021
comcast.com is their corporate mail domain
comcast.net is their customer domain
Both have entirely different mx hosts and won’t relay mail for each other.
From: NANOG <nanog-bounces+ops.lists=gmail.com at nanog.org> on behalf of Matt Hoppes <mattlists at rivervalleyinternet.net>
Sent: Monday, April 19, 2021 10:06:00 PM
To: North American Network Operators' Group <nanog at nanog.org>
Subject: Anyone from Proof Point or Comcast on this list?
It seems we are having trouble sending e-mail to some Comcast customers
and getting a relaying denied message, even though the mail should be
being accepted, not relayed.
Below is a copy of a transcript. Could someone from Proof Point or
Comcast e-mail please contact me to resolve this?
[root at account ~]# dig mx comcast.com
; <<>> DiG 9.11.4-P2-RedHat-9.11.4-16.P2.el7_8.6 <<>> mx comcast.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 32690
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;comcast.com. IN MX
;; ANSWER SECTION:
comcast.com. 9 IN MX 5 mxb-00143702.gslb.pphosted.com.
comcast.com. 9 IN MX 5 mxa-00143702.gslb.pphosted.com.
;; Query time: 0 msec
;; SERVER: 172.16.0.21#53(172.16.0.21)
;; WHEN: Mon Apr 19 12:33:57 EDT 2021
;; MSG SIZE rcvd: 112
[root at account ~]# telnet mxb-00143702.gslb.pphosted.com 25
Connected to mxb-00143702.gslb.pphosted.com.
Escape character is '^]'.
220 mx0b-00143702.pphosted.com ESMTP mfa-m0184889
250 mx0b-00143702.pphosted.com Hello [18.104.22.168], pleased to meet you
mail from:info at rivervalleyinternet.net
250 2.1.0 Sender ok
550 5.7.1 Relaying denied
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the NANOG