Issue Email - How to distinguish password authentication method or connection security to connect to email?

[MHC_1]

Server operating system version

AlmaLinux 9

Plesk version and microupdate number

Plesk Obsidian 18.0.69 Update #3 Web Host Edition

We have a client who can not connect to their Plesk server email address from their iphone, but they can connect from their PC.

The Plesk email settings give me NO INFORMATION about password attributes or encryption, for example what is the connection security ? For example what is the Authentication Method?

The plesk domain --> Mail --> Email --> Mail settings and/or Mail Connection for any address simply don't mention any of these options,

- Where can we see the S/MIME sign status?
- Where can we see if we need encrypt by default (Yes/no)?
- Where can we see password Authentication type (normal pass/ encrypted pass / TLS / NTSM / OAuth2 / etc.
- Where can we see connection security requirements?


Thank you


Jeez.... Why is the Plesk system lacking so many nuances?!!

 

[MHC_1]

I guess no one knows?

 

[learning_curve]

We have a client who can not connect to their Plesk server email address from their iphone, but they can connect from their PC.
~~~

Unwittingly perhaps, you've already answered your own question. There's no issue with the Plesk server e-mail account (on the server itself), because your client can access it from his PC (albeit you've not specified what that is: Windows / Linux / macOS / A.N.Other) The settings on the iPhone will more than likely be the issue here, as they can often be, a bit "fiddly" to connect to some e-mail servers, Plesk, being one of them (sometimes - depending on config). From experience we've connected lots & lots of iPhones to our various Plesk servers. With some subtle iPhone mail Client config changes (and a bit of patience!) they were all connected & have worked very well ever since. There's many, existing online, detailed iPhone mail client, setup tutorials / fault finding guides, which are useful.

FWIW The Plesk guide to the Plesk mail server setup starts here: Mail whilst the actual real setup (via your Plesk Panel), starts here: https://***your-host-domain***:8443/cp/server/mail/settings Then... there's all of the the individual settings by; domain / by subscription type / by individual e-mail account specific settings etc etc and of course, above all of this config, are your OS mail config settings, some of which, you can configure via Plesk, some of which you can't (well some of these, you can actually, but (we think) it's much easier within the OS itself e.g Postfix).

You can perhaps see why, starting this 'fix', by dealing with the Client's own, non-functional device (iPhone) makes a lot of sense (and your Client could have and perhaps should have done this themself, seeing as they have Plesk mail servcie access on another of their own devices aka Factual, local, proof of concept.

 

[MHC_1]

@learning_curve thank you for your reply. Yes, the issue is the iPhone but I can't compare the iPhone connection details to the accepted server details... because the server can't show me what details are being used or required.

I am coming from WHM which has a host of options and a full canon display of connection details.... something Plesk seems to be sorely, sorely lacking. Or even worse that server wide connection details are designated and re-designated across various different spaces, as you mention,

Yes agreed much easier to fix things within the Apps themselves than via Plesk's underwhelming GUI. Anyway. Thank you.

 

[ChristophRo]

For example what is the Authentication Method?

Authentication Method should be set to "Password" in Apple speak (translates to AUTH PLAIN in technical terms) for both incoming and outgoing mail server.
"MD5 Challenge-Response" and "MD5 Digest" may work with most servers as well, but I recommend to not use that.

The "SSL" option/toggle should also be set for both incoming and outgoing mail server. If using port 993/995 it MUST be set.
The same applies for SMTP and when using port 465 or 587, tough technically the later is using "StartTLS" and not "SSL" (but Apple mail products do not care to differ...)

 

[MHC_1]

Authentication Method should be set to "Password" in Apple speak (translates to AUTH PLAIN in technical terms) for both incoming and outgoing mail server.
"MD5 Challenge-Response" and "MD5 Digest" may work with most servers as well, but I recommend to not use that.

The "SSL" option/toggle should also be set for both incoming and outgoing mail server. If using port 993/995 it MUST be set.
The same applies for SMTP and when using port 465 or 587, tough technically the later is using "StartTLS" and not "SSL" (but Apple mail products do not care to differ...)

Thank you.

My question is not about asking you personally what settings should be set. My question is how do I discover these settings for myself from my Plesk Mail setup? THAT is my issue -- that I need to come to this forum and then take the word of another forum user for what value a setting should be! It's crazy.

There is no way on the server that I can see for explicitly setting the Authentication method. Current methods used according to Mail.log are `AUTH` and `PLAIN` as well as something that looks like an MD5 challenge/response method. But again, there's nothing on the Plesk interface to influence these.

 

[ChristophRo]

A current Plesk server does use/support the exact same settings/configuration as 99.999% of all mail servers on this planet.
Well, OK, quite a lot do not support the MD5 stuff anymore, but AUTH PLAIN/LOGIN works literally everywhere and so that is what should be used. (Apple Mail can/does not even distinguish between PLAIN and LOGIN and using the Password option does automatically choose one of them, should the server offer any of both)

Yes, Plesk does not show such settings and you can also not configure them in the GUI.
They simply use the default settings of the software package or your chosen OS.
So you're better of asking Rocky-Linux, Debian, Ubuntu, etc. on what the correct settings for connecting to their Postfix or Dovecot service are.

But if you want really want to know what your mailserver does offer in terms of Authentication Methods, you can check:
- mech_list param /etc/postfix/sasl/smtpd.conf
- auth_mechanisms param in /etc/dovecot/dovecot.conf


Btw. not supporting TLS 1.0/1.1 connections and/or not supporting certain old/obsolete SSL Cipher suites, as well as using an ECDSA SSL certificate (instead of RSA) can also hamper the successful connection of certain (old) mail clients.