OC300 sends localhost in EHLO smtp message, google doesn't like

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OC300 sends localhost in EHLO smtp message, google doesn't like

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OC300 sends localhost in EHLO smtp message, google doesn't like
OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-23 20:41:46 - last edited 2023-11-09 03:42:24
Tags: #Mail Server #SMTP
Model: OC300  
Hardware Version: V1
Firmware Version: 1.19.3 Build 20230906 Rel.38429

 

I'm trying to setup e-mail notifications.

 

When the OC-300 connects to google it does the following:

 

DEBUG SMTP: useEhlo true, useAuth false
DEBUG SMTP: trying to connect to host "smtp-relay.gmail.com", port 25, isSSL false
220 smtp-relay.gmail.com ESMTP o16-20020a81de50000000b005869ca7bcdbsm634088ywl.54 - gsmtp
DEBUG SMTP: connected to host "smtp-relay.gmail.com", port: 25
EHLO localhost
421-4.7.0 Try again later, closing connection. (EHLO)
421-4.7.0  Learn more at
421 4.7.0  https://support.google.com/a/answer/3221692 o16-20020a81de50000000b005869ca7bcdbsm634088ywl.54 - gsmtp
HELO localhost
DEBUG SMTP: EOF: [EOF]

 

It appears that google does not like 'localhost' in the EHLO message.  I've tried w/wo SSL, w/wo AUTHENTICATION, etc.  Always the same response.

 

It there somewhere to configure what hostname the OC-300 sends in that EHLO message?  I have verified this by manually working through an SMTP session with the google relay and it is the localhost that is tripping it up.
 

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#1
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1 Accepted Solution
Re:OC300 sends localhost in EHLO smtp message, google doesn't like-Solution
2023-11-09 03:42:19 - last edited 2023-11-09 03:42:24

Hello @gantzm

 

Thanks for your valuable feedback!

 

After confirming with the support engineer, it doesn't support this kind of domain like "smtp-relay[.]gmail[.]com". I've recorded this request and will report it to the developer team for evaluation.

Best Regards! >> Omada EAP Firmware Trial Available Here << >> Get the Latest Omada SDN Controller Releases Here << *Try filtering posts on each forum by Label of [Early Access]*
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#16
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15 Reply
Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-24 09:31:37

  @gantzm 

 

Do you have a domain? It shouldn't be localhost, it should be a domain.

Share a screenshot of the error message:

421-4.7.0 Try again later, closing connection. (EHLO)
421-4.7.0  Learn more at
421 4.7.0  https://support.google.com/a/answer/3221692 o16-20020a81de50000000b005869ca7bcdbsm634088ywl.54 - gsmtp

Just striving to develop myself while helping others.
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#2
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-24 11:27:31

  @Virgo 

 

You might need to clarify your question.  When I click "SEND" next to "Test SMTP Server" I get an error: "Failed to send the email to the specified recipient."

 

The reason for this is because the controller is sending "localhost" in the EHLO command to the SMTP server.  My destination is using a FQDN.  My Sender Address is using a FQDN, none of which shows up in the EHLO command.

 

Typically the EHLO command is used to identify the host sending the e-mail.  In this case I don't see a way to configure the OC 300 to understand what its FQDN is.

 

 

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#3
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-25 03:28:30

  @gantzm 

 

Oh, you said FQDN, I'm afraid the omada device doesn't support it yet.

Just striving to develop myself while helping others.
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#4
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-25 12:16:27

  @Virgo 

 

Is it possible to get anything except localhost in there?  Even just using omadacontroller would be better.  A lot of SMTP relay servers are not accepting localhost.

 

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#5
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-26 02:54:15

  @gantzm 

 

I'm not sure, hope others in this forum can help you. Is anyone else here?

Just striving to develop myself while helping others.
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#6
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-26 09:36:46

  @gantzm 

need pictures of your error. better to have its source as well. 

i've never seen this on the omada. where did you find it?

DEBUG SMTP: useEhlo true, useAuth false
DEBUG SMTP: trying to connect to host "smtp-relay.gmail.com", port 25, isSSL false
220 smtp-relay.gmail.com ESMTP o16-20020a81de50000000b005869ca7bcdbsm634088ywl.54 - gsmtp
DEBUG SMTP: connected to host "smtp-relay.gmail.com", port: 25
EHLO localhost
421-4.7.0 Try again later, closing connection. (EHLO)
421-4.7.0  Learn more at
421 4.7.0  https://support.google.com/a/answer/3221692 o16-20020a81de50000000b005869ca7bcdbsm634088ywl.54 - gsmtp
HELO localhost
DEBUG SMTP: EOF: [EOF]

 

and also need your config, the page on omada.

 

421 is a code telling the server is not available. 

Response codes that start with 4 and are errors, and the number indicates the error type. Errors that start with a 4 are temporary failures. No action is needed, the sender will try again. Errors that start with 5 are permanent failures and action is required to fix the problem.

 

So, is this a problem with the recipient?

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
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#7
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-26 13:21:08

  @Tedd404 

 

That error comes from the controller logs that you can download from the controller UI.  The actual log file is either server.log or startup.log.

 

The error number from the SMTP relay is rather misleading, to say the least.

 

When I manually emulate that session with telnet ( very easy to do with SMTP ) I find that if I use anything other than localhost in EHLO message the session works fine.

 

I believe this is an attempt by several SMTP relays to start cutting back on spam and refusing to accept connections from devices that identify as 'localhost'.

 

 

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#8
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-27 00:58:45

  @gantzm 

sorry i am confused by your localhost constantly mentioned in the replies. is there any picture to illustrate this localhost? 

i don't think there should be a localhost involved in this. it's mail service and for no reason you should use localhost in it. 

so the issue now is that people don't understand your question and cannot provide any further insights into your issue. i am out of options. expect someone else. 

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
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#9
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-27 12:32:31

  @Tedd404 

 

I would love to post exact details on how to reproduce this but the forum software won't let me.  Everytime I try and post the steps and results the forum tells me I'm trying to post "links" to external sites.  Even if I try and attach the steps as a file it fails.

 

I've tried to "edit" things so they don't look like links but the forum still won't let me post it.

 

Well I can't even add a link to Pastebin.

 

If you go to pastebin and add "YqGrEqBi" to the url maybe this will work.

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#10
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Re:OC300 sends localhost in EHLO smtp message, google doesn't like
2023-10-30 09:56:25

  @gantzm 

i don't want to register a new account. 

try this format to paste. no external links are allowed.

xyz[dot]net

ScReW yOu gUyS. I aM GOinG hoMe. —————————————————————— For heaven's sake, can you write and describe your issue based on plain fact, common logic and a methodologic approach? Appreciate it.
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#11
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