Email sending issue (was: URGENT)

[jdaviescoates]

In a post on an originally unrelated thread about IPv6 issues @Gengar posted this link https://www.spamhaus.com/resource-center/successfully-accessing-spamhauss-free-block-lists-using-a-public-dns/ which I think explains what's going on with all these false positive spamhaus issues people are having:

The TL;DR seems to be: fill in this form https://www.spamhaus.com/free-trial/sign-up-for-a-free-data-query-service-account/

[nebulon]

@mmtrade are you able to connect to your mails service, if you run telnet via SSH on your server?

telnet 172.18.30.4 2525

[d19dotca]

@mmtrade said in URGENT:

@nebulon Well that is what i do not understand whats going on??

How can I rectify this?

Everything is okay but the mail is not sending or receiving. This has nothing to do with my service provider.

When you say it isn’t sending or receiving… what happens when you try to send email exactly? And for receiving… are the senders getting a bounce back message? If yes, what does the bounce back say?

When you try to send… are you getting an automated error response back? Is your mail client showing a failure to connect to the SMTP server?

We need more information for anyone to help.

Are you certain your DNS records show the correct IP of your server for mail.{your domain.tld} and was that changed recently at all?

Is it possible your IP address is intermittently being blocklisted where it is showing listed and then later on is showing fine, and keeps flip flopping like that perhaps? The blocklist alert in Cloudron has no bearing on your actual mail functionality, it especially won’t have anything to do with receiving mail from others. If on a blocklist it still won’t impact your ability to send unless the receiving end is blocking it due to being on the blocklist, or may be delivered but found in spam boxes instead.

[mmtrade]

@mmtrade @nebulon @d19dotca

I deleted my whole server and started the reinstallation process again with a different host. Now it started working and sending mails. When i started my campaign, I noticed i could not send up to 1000 emails before this issue started again. I am being blocked and my emails will not receive or send. when i try to do a test it does not work and it still keeps showing me the attached. Everything just worked fine when i started the process again but i do not know why after some time i am being blocked....

Please i need answers to this urgently because I am loosing my mind.

I bet you if i start it all over again it will work and after some time it will stop working

whats going on and is this a new update with cloudrun

i have contacted VPS server provider and actually they do not block or alter any ports so this has to be a cloudron issue. If so why would it work then later stop

Is there any restrictions with this new upgraded cloudron??? the other versions never did this before. It was easy and fun

[mmtrade]

see attached i changed host names

[d19dotca]

@mmtrade said in URGENT:

Now it started working and sending mails. When i started my campaign, I noticed i could not send up to 1000 emails before this issue started again. I am being blocked and my emails will not receive or send. when i try to do a test it does not work and it still keeps showing me the attached. Everything just worked fine when i started the process again but i do not know why after some time i am being blocked....

This definitely sounds like rate limiting being done somewhere if you get up to 1000 emails and then suddenly you can't send any more. But I'm not sure why you can't receive emails either. This feels like something to do with the host you're running with, but if they say they don't do that then I'm not so sure where else it could come from.

What do the mail service logs show? Does the issue happen even after you restart the server or restart the mail service? If yes, then that would seem like something outside of Cloudron, but if the issue is then resolved after restarting then perhaps something else within Cloudron that's affecting things. Best bet to help narrow it down is to show the logs from the mail server (redact sensitive info like email addresses though of course). You may feel safer sending those logs into Cloudron Support email instead from an alternative address.

[mmtrade]

My bad it sent more than 1000 but it was just an odd number. I think about 5436 emails to be precise. the last one sent around 10k plus.

the random changes in sending emails makes it suspicious.

However at first it was the IP spamhous block issue which got resolved and still it did not work moving forward before i reinstalled it and set another host to it.

Does it mean that cloudrun has detected the IP? what do you need from me to test and know cloudrun is not associated with this issue?

What do the mail service logs show? I cannot send emails out to know this. If you know how to get this let me know. I will post what you need me to on forum.

Even when i restart the server.. the issue is still there.

Tell me what to do

[mmtrade]

@d19dotca @BrutalBirdie @jdaviescoates

My bad it sent more than 1000 but it was just an odd number. I think about 5436 emails to be precise. the last one sent around 10k plus.

the random changes in sending emails makes it suspicious.

However at first it was the IP spamhous block issue which got resolved and still it did not work moving forward before i reinstalled it and set another host to it.

Does it mean that cloudrun has detected the IP? what do you need from me to test and know cloudrun is not associated with this issue?

What do the mail service logs show? I cannot send emails out to know this. If you know how to get this let me know. I will post what you need me to on forum.

Even when i restart the server.. the issue is still there.

Tell me what to do

[d19dotca]

@mmtrade said in URGENT:

What do the mail service logs show? I cannot send emails out to know this. If you know how to get this let me know. I will post what you need me to on forum.

In Cloudron, you click on Services page and then the log icon for the mail container. Then export the logs (in case the issue isn't most recently seen in the logs).

[nebulon]

@mmtrade since you are sending out lots of emails and probably within a very short time, you pretty much have to use some external email relay, otherwise your Cloudron's IP will end up in blocklists and gets flagged, at which point it is hard to build up trust with other email providers for that IP again. All kinds of issues will come up once the IP of the sending email server (your Cloudron) gets a bad reputation and the errors other mail providers give aren't always too helpful, dependin gon their spam protection strategy.

This is bound to your IP btw, so restart a server or so won't help.

Basically for non-transaction emails you want to use one of the supported relays https://docs.cloudron.io/email/#relay-outbound-mails there is nothing we can do much on the platform code side unfortunately.

[mmtrade]

@d19dotca

you mean this??

[jdaviescoates]

@mmtrade said in Email sending issue (was: URGENT):

I deleted my whole server and started the reinstallation process again with a different host. Now it started working and sending mails. When i started my campaign, I noticed i could not send up to 1000 emails before this issue started again. I am being blocked and my emails will not receive or send. when i try to do a test it does not work and it still keeps showing me the attached. Everything just worked fine when i started the process again but i do not know why after some time i am being blocked....

Please i need answers to this urgently because I am loosing my mind.

From what you've said here, it sounds to me like this has nothing to do with Cloudron.

It's likely because your hosts are blocking port 25, either because they do that by default (lots do - e.g. these days Hetzner does that with new customers), or because you're trying to send 1000s emails quickly and that's triggering anti spamming protection and the block is getting enabled.

If you need to send lots of emails you're much better off outsourcing that to a specialist email sending service like https://postmarkapp.com/ etc (I'm using mailgun.com just because that's what Ghost requires but lot of people here have had good experiences with Post Mark)

[jdaviescoates]

@mmtrade no @d19dotca means here:

But this clearly isn't anything to do with Cloudron imho. You need to use an email relay if you're going to be sending out 1000s of emails, otherwise you'll get blocked by your host and/ or added to blacklists. There isn't anything Cloudron can do about that, it's just the way the email world works.

[mmtrade]

@nebulon This is from cloudron server

I cannot run telnet on it

i changed service providers and same thing and same issue

[mmtrade]

@jdaviescoates this is 100% cloudrun issue

i changed servers just to be sure and i still have thesame error messsage assame as last VPS server

i tried connecting to telnet not working

this messed my email campaign up.. i also put it some triggers to make sure it does not come into spam and send emails at the rate off 200 per 30 mins.

see attached

the problem is from cloudron and you need to fix this. This is no server issue. Since you made your upgrade it has messed our servers up.Check this internally because this same issue cannot happen with a different VPS provider

[d19dotca]

@mmtrade Again, you’ll want to check the mail container status and logs, as that will likely be the most telling if the issue is in Cloudron or not. Maybe include a screenshot of the services list, and include a snippet of the latest log lines before and after restarting the mail container. That will probably be helpful.

[mmtrade]

@d19dotca can you tell me how to check this?

[d19dotca]

@mmtrade @jdaviescoates showed how to do that above. Go to Services page and click the log icon next to the mail line.

[mmtrade]

@d19dotca can you give me a SC on this

[mmtrade]

I mean can you give me Screeshots for this review? Do you think this problem can come from the OS?