XF 1.5 Delayed Two-Step-Verifaction eMails

[Freelancer]

Recently more and more of my users reported delayed (up to 40 minutes) or missing Two-Step-Verification eMails. I contacted the service provider (I am using SMTP sending from XF) and they told me everything would be okay on their end, no logs showed any problems. I also did check the Server logs and XF logs but can't find anything odd or any error beside some bounced eMails from the past, but nothing related to the Two-Step-Verification.

Is there something that could block the Two-Step-Verifaction or delaying eMails on the code side? Can add-ons influence it? Where would I need to look?

Thanks in advance

 

[Mouth]

I contacted the service provider (I am using SMTP sending from XF) and they told me everything would be okay on their end, no logs showed any problems

But what did the logs show? Delivery of the mail to the recipients mail server immediately after your provider received it?

 

[Freelancer]

The Server logs do not show any eMail error. Are they supposed to show any eMail delivery? I do only have access to the error logs.

 

[Mouth]

You are making an SMTP connection to your providers mail server. They are accepting your email, and their server will then make an SMTP connection to the recipients mail server to deliver your email.
Thus, the providers mail logs should show x2 actions - 1 for accepting the email from you, and 2 for delivering that email to the target/recipient server.
Timestamps on each action will be what you want to know, along with the exact time your user/server actioned the 2FA email launch.

 

[Freelancer]

Okay, I think the provider did not give me that particular info. I will ask them again. Thank you for the hint.

 

[Freelancer]

So, bad thing is I am on a "shared" host and the provider has a hard time picking up my stuff from the mailserver logs. But I think I found something that could explain the problems.
I made my own test and did simulate an impatient user... When there is some traffic and the eMail does not arrive instantly, some users try to login again and again... the system sends out another and another eMail and these are then delayed. I guess that is the mail queue of XF that prevents spam? It could be an explanation. On my part I did not experience any problems, but users come up with the weirdest behaviors and blame the software.

 

[Pieman]

You could move the forum email to something like Amazon SES, which once set up has excellent delivery rates and times, it will cost but it's only $0.10 / 1000 emails.

 

[Freelancer]

I will look into this. Sounds good.

 

[Paul B]

I guess that is the mail queue of XF that prevents spam?

XF doesn't have a spam prevention mail queue.

Emails are handed off to the server immediately and from there it's down to your server and any steps in between before it lands in the user's mailbox.

 

[Freelancer]

That is really strange. Because quite a few Users reported delayed eMails while the Hosting Provider says there are no errors logged and I also had no significant delays with my tests. Maybe it is just internet traffic and a shared server. I wanted to switch to a managed server in the future and see how performance improves.