I have a category with a ‘Custom incoming email address’ set – [CATEGORY]@forum.tasat.org When I email directly from Gmail to the address, messages are processed as expected and land in the category. mail-receiver logs on success: Oct 30 05:26:43 forum-mail-receiver postfix/smtpd[76028]: connect from mail-ot1-f46.google.com[209.85.210.46] Oct 30 05:26:43 forum-mail-receiver postfix/smtpd[76028]: B5B78309A1E: client=mail-ot1-f46.google.com[209.85.210.46] Oct 30 05:26:43 forum-mail-receiver postfix/cleanup[76035]: B5B78309A1E: message-id= Oct 30 05:26:43 forum-mail-receiver postfix/qmgr[98]: B5B78309A1E: from= , size=3056, nrcpt=1 (queue active) Oct 30 05:26:43 forum-mail-receiver postfix/smtpd[76028]: disconnect from mail-ot1-f46.google.com[209.85.210.46] ehlo=1 mail=1 rcpt=1 bdat=1 quit=1 commands=5 Oct 30 05:26:43 receive-mail[76037]: Recipient: [CATEGORY]@forum.tasat.orgOct 30 05:26:44 forum-mail-receiver postfix/pipe[76036]: B5B78309A1E: to= , relay=discourse, delay=0.57, delays=0.23/0.02/0/0.32, dsn=2.0.0, status=sent (delivered via discourse service) Oct 30 05:26:44 forum-mail-receiver postfix/qmgr[98]: B5B78309A1E: removed But when I submit a message to [CATEGORY]@forum.tasat.org, with identical contents, from a contact form at our landing page on carrd.co, it is not processed. mail-receiver logs on failure: Oct 30 06:47:20 forum-mail-receiver postfix/smtpd[76057]: connect from a69-230.smtp-out.amazonses.com[54.240.69.230] Oct 30 06:47:20 forum-mail-receiver postfix/smtpd[76057]: lost connection after EHLO from a69-230.smtp-out.amazonses.com[54.240.69.230] Oct 30 06:47:20 forum-mail-receiver postfix/smtpd[76057]: disconnect from a69-230.smtp-out.amazonses.com[54.240.69.230] ehlo=1 commands=1 Apparently the EHLO command is used to “Identify the domain name of the sending host to SMTP”. I don’t know where to go with this. What would cause EHLO to fail? Do I have to whitelist SES or something..?

Well, I didn’t get any supporting information from carrd.co except they claimed to use “opportunitistic TLS” that should fall back to an unencrypted connection. The one mail server health test that I wasn’t passing was the SMTP banner didn’t match the domain provided by the reverse DNS PTR record. Elsewhere on meta I turned up the idea of adding to mail-receiver.yml under env: POSTCONF_smtpd_banner: forum.tasat.org ESMTP $mail_name This resolved the flag re. SMTP banner mismatch, and the incoming mail failures changed from disconnecting at HELO to disconnecting at STARTTLS. I finally enabled TLS, and email from the contact form comes through. With the process now working, though, it’s illuminated some flaws in my whole idea of ingesting topics via a web form. But that’ll be another topic.

[image] ToddZ: I don’t know where to go with this. What would cause EHLO to fail? Do I have to whitelist SES or something…? EHLO likely didn’t fail; postfix is saying that the sending end sent an EHLO and then dropped the connection. Something like this: [baron ~]$ telnet forum.tasat.org 25 Trying 64.176.213.39... Connected to forum.tasat.org. Escape character is '^]'. 220 ESMTP server EHLO baron 250-forum-mail-receiver.localdomain 250-PIPELINING 250-SIZE 10240000 250-VRFY 250-ETRN 250-ENHANCEDSTATUSCODES 250-8BITMIME 250-DSN 250 CHUNKING ^] telnet> quit (you’ll probably see a similar message in your logs referencing my IP) This is a problem on SES’s end. I’d advise watching the traffic coming in on port 25 to see if there’s any indication why it dropped, or check SES to see if it has any logs.

Thanks supermathie – I don’t have access to carrd.co’s SES logs, but I have port 25 logs from another failed attempt. (Wish I knew how to interpret.) Anything jump out at you here..? SES failure - Discourse mail-receiver log Oct 30 16:50:11 forum-mail-receiver postfix/anvil[76091]: statistics: max connection count 1 for (smtp:159.203.42.156) at Oct 30 16:46:35 Oct 30 16:50:11 forum-mail-receiver postfix/anvil[76091]: statistics: max cache size 1 at Oct 30 16:46:35 Oct 30 17:49:01 forum-mail-receiver postfix/smtpd[76093]: connect from a69-230.smtp-out.amazonses.com[54.240.69.230] Oct 30 17:49:01 forum-mail-receiver postfix/smtpd[76093]: lost connection after EHLO from a69-230.smtp-out.amazonses.com[54.240.69.230] Oct 30 17:49:01 forum-mail-receiver postfix/smtpd[76093]: disconnect from a69-230.smtp-out.amazonses.com[54.240.69.230] ehlo=1 commands=1 root@forum:/var/discourse# SES failure - Wireshark port 25 log No. Time Source Destination Protocol Length Info 11913 85.864926 54.240.69.230 64.176.213.39 TCP 74 50903 → 25 [SYN] Seq=0 Win=26883 Len=0 MSS=1460 SACK_PERM TSval=1554444054 TSecr=0 WS=128 11914 85.865305 64.176.213.39 54.240.69.230 TCP 74 25 → 50903 [SYN, ACK] Seq=0 Ack=1 Win=43440 Len=0 MSS=1460 SACK_PERM TSval=958362575 TSecr=1554444054 WS=1024 11921 85.871994 54.240.69.230 64.176.213.39 TCP 66 50903 → 25 [ACK] Seq=1 Ack=1 Win=27008 Len=0 TSval=1554444061 TSecr=958362575 12239 86.221038 64.176.213.39 54.240.69.230 SMTP 84 S: 220 ESMTP server 12245 86.227770 54.240.69.230 64.176.213.39 TCP 66 50903 → 25 [ACK] Seq=1 Ack=19 Win=27008 Len=0 TSval=1554444417 TSecr=958362931 12246 86.228748 54.240.69.230 64.176.213.39 SMTP 103 C: EHLO a69-230.smtp-out.amazonses.com 12247 86.228791 64.176.213.39 54.240.69.230 TCP 66 25 → 50903 [ACK] Seq=19 Ack=38 Win=44032 Len=0 TSval=958362939 TSecr=1554444418 12248 86.228963 64.176.213.39 54.240.69.230 SMTP 220 S: 250-forum-mail-receiver.localdomain | PIPELINING | SIZE 10240000 | VRFY | ETRN | ENHANCEDSTATUSCODES | 8BITMIME | DSN | CHUNKING 12253 86.236796 54.240.69.230 64.176.213.39 TCP 66 50903 → 25 [FIN, ACK] Seq=38 Ack=173 Win=28032 Len=0 TSval=1554444426 TSecr=958362939 12254 86.237257 64.176.213.39 54.240.69.230 TCP 66 25 → 50903 [FIN, ACK] Seq=173 Ack=39 Win=44032 Len=0 TSval=958362947 TSecr=1554444426 12257 86.243960 54.240.69.230 64.176.213.39 TCP 66 50903 → 25 [ACK] Seq=39 Ack=174 Win=28032 Len=0 TSval=1554444433 TSecr=958362947 For comparison: Gmail success - Wireshark port 25 log No. Time Source Destination Protocol Length Info 1173638 893.998102 162.142.125.93 64.176.213.39 TCP 74 27763 → 25 [SYN] Seq=0 Win=42340 Len=0 MSS=1460 SACK_PERM TSval=1729720003 TSecr=0 WS=1024 1173639 893.998341 64.176.213.39 162.142.125.93 TCP 74 25 → 27763 [SYN, ACK] Seq=0 Ack=1 Win=43440 Len=0 MSS=1460 SACK_PERM TSval=2319295245 TSecr=1729720003 WS=1024 1173667 894.015884 162.142.125.93 64.176.213.39 TCP 54 27763 → 25 [RST] Seq=1 Win=0 Len=0 1178853 897.638926 162.142.125.207 64.176.213.39 TCP 74 60246 → 25 [SYN] Seq=0 Win=21900 Len=0 MSS=1460 SACK_PERM TSval=1654559109 TSecr=0 WS=1024 1178855 897.639088 64.176.213.39 162.142.125.207 TCP 74 25 → 60246 [SYN, ACK] Seq=0 Ack=1 Win=43440 Len=0 MSS=1460 SACK_PERM TSval=461108143 TSecr=1654559109 WS=1024 1178884 897.656814 162.142.125.207 64.176.213.39 TCP 66 60246 → 25 [ACK] Seq=1 Ack=1 Win=22528 Len=0 TSval=1654559127 TSecr=461108143 1179106 897.805588 64.176.213.39 162.142.125.207 SMTP 84 S: 220 ESMTP server 1179134 897.823322 162.142.125.207 64.176.213.39 TCP 66 60246 → 25 [ACK] Seq=1 Ack=19 Win=22528 Len=0 TSval=1654559293 TSecr=461108310 1179139 897.825315 162.142.125.207 64.176.213.39 SMTP 86 C: EHLO www.censys.io 1179140 897.825350 64.176.213.39 162.142.125.207 TCP 66 25 → 60246 [ACK] Seq=19 Ack=21 Win=44032 Len=0 TSval=461108329 TSecr=1654559295 1179142 897.825495 64.176.213.39 162.142.125.207 SMTP 220 S: 250-forum-mail-receiver.localdomain | PIPELINING | SIZE 10240000 | VRFY | ETRN | ENHANCEDSTATUSCODES | 8BITMIME | DSN | CHUNKING 1179173 897.844902 162.142.125.207 64.176.213.39 SMTP 76 C: STARTTLS 1179174 897.845039 64.176.213.39 162.142.125.207 SMTP 108 S: 502 5.5.1 Error: command not implemented 1179207 897.865559 162.142.125.207 64.176.213.39 TCP 66 60246 → 25 [FIN, ACK] Seq=31 Ack=215 Win=22528 Len=0 TSval=1654559335 TSecr=461108349 1179208 897.865879 64.176.213.39 162.142.125.207 TCP 66 25 → 60246 [FIN, ACK] Seq=215 Ack=32 Win=44032 Len=0 TSval=461108370 TSecr=1654559335 1179237 897.883702 162.142.125.207 64.176.213.39 TCP 66 60246 → 25 [ACK] Seq=32 Ack=216 Win=22528 Len=0 TSval=1654559353 TSecr=461108370 1423203 1062.340039 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980279080 TSecr=0 WS=256 1424699 1063.379486 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980280120 TSecr=0 WS=256 1426247 1064.403473 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980281144 TSecr=0 WS=256 1427782 1065.427579 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980282168 TSecr=0 WS=256 1429343 1066.451555 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980283192 TSecr=0 WS=256 1430904 1067.475717 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980284216 TSecr=0 WS=256 1433947 1069.523326 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980286264 TSecr=0 WS=256 1440507 1073.555346 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980290296 TSecr=0 WS=256 1452771 1081.619544 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980298360 TSecr=0 WS=256 1476480 1098.003562 2001:4860:4864:20::33 2001:19f0:1000:68ec:5400:4ff:fe92:8e2b TCP 94 [TCP Retransmission] 45423 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1440 SACK_PERM TSval=980314744 TSecr=0 WS=256 1511662 1122.242370 209.85.160.45 64.176.213.39 TCP 74 45424 → 25 [SYN] Seq=0 Win=65535 Len=0 MSS=1412 SACK_PERM TSval=806841994 TSecr=0 WS=256 1511663 1122.242862 64.176.213.39 209.85.160.45 TCP 74 25 → 45424 [SYN, ACK] Seq=0 Ack=1 Win=43440 Len=0 MSS=1460 SACK_PERM TSval=51132547 TSecr=806841994 WS=1024 1511715 1122.273627 209.85.160.45 64.176.213.39 TCP 66 45424 → 25 [ACK] Seq=1 Ack=1 Win=269824 Len=0 TSval=806842025 TSecr=51132547 1511825 1122.343466 64.176.213.39 209.85.160.45 SMTP 84 S: 220 ESMTP server 1511876 1122.374090 209.85.160.45 64.176.213.39 TCP 66 45424 → 25 [ACK] Seq=1 Ack=19 Win=269824 Len=0 TSval=806842125 TSecr=51132647 1511877 1122.374242 209.85.160.45 64.176.213.39 SMTP 96 C: EHLO mail-oa1-f45.google.com 1511878 1122.374276 64.176.213.39 209.85.160.45 TCP 66 25 → 45424 [ACK] Seq=19 Ack=31 Win=44032 Len=0 TSval=51132678 TSecr=806842126 1511880 1122.374429 64.176.213.39 209.85.160.45 SMTP 220 S: 250-forum-mail-receiver.localdomain | PIPELINING | SIZE 10240000 | VRFY | ETRN | ENHANCEDSTATUSCODES | 8BITMIME | DSN | CHUNKING 1511929 1122.405234 209.85.160.45 64.176.213.39 SMTP 112 C: MAIL FROM: SIZE=3017 1511930 1122.405311 209.85.160.45 64.176.213.39 SMTP 102 C: RCPT TO: 1511931 1122.405404 64.176.213.39 209.85.160.45 TCP 66 25 → 45424 [ACK] Seq=173 Ack=113 Win=44032 Len=0 TSval=51132709 TSecr=806842157 1511932 1122.405532 209.85.160.45 64.176.213.39 SMTP 2866 C: BDAT 3017 LAST | DATA fragment, 2784 bytes 1511933 1122.405660 209.85.160.45 64.176.213.39 SMTP/IMF 299 from: Todd Zimmerman , subject: Space operas where the hero is not a "Chosen One", (text/plain) (text/html) 1511993 1122.446635 64.176.213.39 209.85.160.45 TCP 66 25 → 45424 [ACK] Seq=173 Ack=3146 Win=41984 Len=0 TSval=51132751 TSecr=806842157 1512387 1122.715764 64.176.213.39 209.85.160.45 SMTP 94 S: 250 2.1.0 Ok | 250 2.1.5 Ok 1512445 1122.751435 209.85.160.45 64.176.213.39 TCP 66 45424 → 25 [ACK] Seq=3146 Ack=201 Win=269824 Len=0 TSval=806842503 TSecr=51133020 1512446 1122.751497 64.176.213.39 209.85.160.45 SMTP 114 S: 250 2.0.0 Ok: 3017 bytes queued as 3D37D309944 1512497 1122.782171 209.85.160.45 64.176.213.39 TCP 66 45424 → 25 [ACK] Seq=3146 Ack=249 Win=269824 Len=0 TSval=806842534 TSecr=51133055 1512499 1122.783518 209.85.160.45 64.176.213.39 SMTP 72 C: QUIT 1512500 1122.783562 64.176.213.39 209.85.160.45 TCP 66 25 → 45424 [ACK] Seq=249 Ack=3152 Win=43008 Len=0 TSval=51133087 TSecr=806842535 1512501 1122.783584 209.85.160.45 64.176.213.39 TCP 66 45424 → 25 [FIN, ACK] Seq=3152 Ack=249 Win=269824 Len=0 TSval=806842535 TSecr=51133055 1512503 1122.783969 64.176.213.39 209.85.160.45 SMTP 81 S: 221 2.0.0 Bye 1512504 1122.783994 64.176.213.39 209.85.160.45 TCP 66 25 → 45424 [FIN, ACK] Seq=264 Ack=3153 Win=43008 Len=0 TSval=51133088 TSecr=806842535 1512555 1122.814604 209.85.160.45 64.176.213.39 TCP 54 45424 → 25 [RST] Seq=3153 Win=0 Len=0

[image] ToddZ: 12246 86.228748 54.240.69.230 64.176.213.39 SMTP 103 C: EHLO a69-230.smtp-out.amazonses.com 12247 86.228791 64.176.213.39 54.240.69.230 TCP 66 25 → 50903 [ACK] Seq=19 Ack=38 Win=44032 Len=0 TSval=958362939 TSecr=1554444418 12248 86.228963 64.176.213.39 54.240.69.230 SMTP 220 S: 250-forum-mail-receiver.localdomain | PIPELINING | SIZE 10240000 | VRFY | ETRN | ENHANCEDSTATUSCODES | 8BITMIME | DSN | CHUNKING 12253 86.236796 54.240.69.230 64.176.213.39 TCP 66 50903 → 25 [FIN, ACK] Seq=38 Ack=173 Win=28032 Len=0 TSval=1554444426 TSecr=958362939 SES closes the connection in packet 12253 (FIN) for reasons known only to it. As to why, this is something about which you’ll need to inquire to AWS.

Email to custom address fails: "lost connection after EHLO"

Product Support

ToddZ October 31, 2024, 9:04pm 5

Much appreciated! I’ve asked carrd.co support to check logs, but they’re apparently based in a neighboring solar system. It may be a while before I have more info.

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Email to custom address fails: "lost connection after EHLO"

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