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SMTP check not working with TCP

See original GitHub issue

Getting the following response on a SMTP port check (587 as well as 465)

connect EHOSTUNREACH xx.xx.xx.xx:587

The IP listed in the error above is my IP for my server.

(node:19) UnhandledPromiseRejectionWarning: Error: connect EHOSTUNREACH 142.251.2.109:587
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1148:16)
(node:19) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 62)

I checked that IP in the log, and it looks like it belongs to google? It is not the IP of any of my servers.

https://www.whois.com/whois/142.251.2.109

Issue Analytics

State:
Created 2 years ago
Comments:11 (4 by maintainers)

Top GitHub Comments

1reaction

0mnicommented, Jul 12, 2021

Is it possible that your ISP is blocking something? Testing on my end from two different servers, it works as expected as well.

If it’s a server in a lab on your own network and you’re trying to access it through your own external IP, you router could be blocking hairpinning requests. https://en.wikipedia.org/wiki/Hairpinning

It’s running on a VPS, have it working with other services going to the same host with no issues.

0reactions

0mnicommented, Jul 12, 2021

Seems like the host is doing something “funky” … Put in a ticket. Thanks all!

|18:38:09|root@status2:[/opt/uptime-kuma]> traceroute mail.danlee.ca
traceroute to mail.danlee.ca (192.210.243.56), 30 hops max, 60 byte packets
 1  ionica.meet-your-dream.live (185.232.15.122)  0.063 ms  0.038 ms  0.035 ms
 2  23.147.224.21 (23.147.224.21)  0.210 ms  0.273 ms  0.239 ms
 3  border1.ae4.dedipath-lacp.lax014.pnap.net (69.88.129.105)  0.374 ms  0.360 ms  0.310 ms
 4  core1.po1-40g-bbnet1.lax012.pnap.net (216.52.255.14)  1.371 ms core1.po2-40g-bbnet2.lax012.pnap.net (216.52.255.73)  1.600 ms  1.605 ms
 5  e0-11.cr1.lax2.us.unitasglobal.net (198.232.115.137)  1.559 ms  2.127 ms  1.756 ms
 6  ip4.gtt.net (209.120.155.53)  0.804 ms  0.847 ms  0.806 ms
 7  ae3.cr1-buf1.ip4.gtt.net (89.149.185.197)  56.253 ms be2930.ccr21.elp01.atlas.cogentco.com (154.54.42.78)  21.336 ms ae3.cr1-buf1.ip4.gtt.net (89.149.185.197)  56.689 ms
 8  78.152.61.29 (78.152.61.29)  63.353 ms 78.152.57.87 (78.152.57.87)  62.554 ms 78.152.61.29 (78.152.61.29)  63.275 ms
 9  * * *
10  * * *
11  * * *
12  mail.danlee.ca (192.210.243.56)  62.724 ms  62.736 ms  62.810 ms
|18:38:33|root@status2:[/opt/uptime-kuma]> telnet mail.danlee.ca 587
Trying 192.210.243.56...
telnet: Unable to connect to remote host: No route to host
|18:38:38|root@status2:[/opt/uptime-kuma]> telnet mail.danlee.ca 80
Trying 192.210.243.56...
Connected to mail.danlee.ca.
Escape character is '^]'.
^]
HTTP/1.1 400 Bad Request
Server: nginx
Date: Mon, 12 Jul 2021 22:38:55 GMT
Content-Type: text/html; charset=utf-8
Content-Length: 150
Connection: close
X-Frame-Options: SAMEORIGIN

<html>
<head><title>400 Bad Request</title></head>
<body>
<center><h1>400 Bad Request</h1></center>
<hr><center>nginx</center>
</body>
</html>
Connection closed by foreign host.

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