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Resolved Port 25 closed cannot send email

Seba

Basic Pleskian
I've switched to Ionos cloud server and for security reason they close the port 25, I don't have any mail servers on my server so I don't really care BUT my problem is that I cannot send email from the server to myself.

I'm speaking about Watchdog and Clamav, in clamav I use
Code:
mail -s ...
to send the report to an email.

I've already followed this guide to use port 587 but is not working, yes I've added a TCP 587 in the firewall in Ionos, do I need to add the same port in the Plesk firewall?

How to enable 587 submission port on Plesk server (Linux)?

I can see the email in the mail queue and they appear as deffer.

I'm using the default firewall policy for the moment, but I've actually a strengths one before, so I can even disable it that it doesn't really change too much as everything is filtered before hand with the firewall in Ionos where I have open just some ports.

I don't know if it has something to do but my server hostname is of a domain that is behind a load balancers so is not pointing direclty to the server, in the DNS i have the load balancers IP and the in the load balancers the 2 servers.
 
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Incoming email will always be over Port 25.

You need to contact Ionos and request for them to unblock the port.
 
Incoming email will always be over Port 25. You need to contact Ionos and request for them to unblock the port.
^^ Exactly what he said.
However, if you're using IONOS Cloud Servers (as we do) you can open or close all ports, via the IONOS Cloud Panel / Server / Network / Firewall Policies / Linux (or Windows :confused:) yourself @Seba You don't need IONOS to do that for you unless... You've chosen an IONOS "Managed Service Solution' Cloud Server(s), in which case, you will need them to do it.
 
Incoming email will always be over Port 25.

You need to contact Ionos and request for them to unblock the port.

As I said we don't have any mail server so I don't care, I just want to be able to send email from the server to our company for monitoring purpose like watchdog and the antivirus.
 
^^ Exactly what he said.
However, if you're using IONOS Cloud Servers (as we do) you can open or close all ports, via the IONOS Cloud Panel / Server / Network / Firewall Policies / Linux (or Windows :confused:) yourself @Seba You don't need IONOS to do that for you unless... You've chosen an IONOS "Managed Service Solution' Cloud Server(s), in which case, you will need them to do it.

We are not using the managed cloud so I can manage the firewall, Incoming emails are on port 25, what about outgoing email? that is what exactly I need. I just need watchdog and the antivirus to send email to me for monitoring purpose, we use an external email API to send emails.
 
....if you're using IONOS Cloud Servers (as we do) you can open or close all ports, via the IONOS Cloud Panel / Server / Network / Firewall Policies / Linux ...
Once you've configured you're IONOS server ports correctly, you can then configure your Plesk firewall and your Plesk mail services correctly (to work with your chosen setup) :)
 
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That's covered in my original reply:
Once you've configured you're IONOS server ports correctly, you can then configure your Plesk firewall and your Plesk mail services correctly (to work with your chosen setup) :)

So I opened port 25 and 587 as I selected
Enable SMTP service on port 587 on all IP addresses
in the Ionos firewall, disabled the Plesk firewall and tried to send email with sendmail through command line but nothing to do, still doesn't send email.

I've also change the
Outgoing mail mode
and set "Send from the specified IP addresses" and choose the server IP as the only website that I have is behind a load balancers

What I have all the time in the log file is
connection time out / no route to host
 
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Solved, you need to contact them, even if you open it in the firewall they blocked it and actually I can send email without open it in the firewall.
my firewall doesn't contain any 25 or 587 port but still I'm able to send emails now, probably i cannot receive but I don't care as we just want to send report from the server to our office.
 
Solved, you need to contact them, even if you open it in the firewall they blocked it and actually I can send email without open it in the firewall. my firewall doesn't contain any 25 or 587 port but still I'm able to send emails now, probably i cannot receive but I don't care as we just want to send report from the server to our office.
Cool! It's good that you can now achieve what you wanted.

It's quite odd though, as we've never had to contact IONOS about "...Open Cloud Server Ports That Are Still Blocked By IONOS..." If yours is a relatively new IONOS contract, then maybe... it's a recent IONOS 'rule addition' but only for new server placements? We'll double check on the next one that we take on!
 
Cool! It's good that you can now achieve what you wanted.

It's quite odd though, as we've never had to contact IONOS about "...Open Cloud Server Ports That Are Still Blocked By IONOS..." If yours is a relatively new IONOS contract, then maybe... it's a recent IONOS 'rule addition' but only for new server placements? We'll double check on the next one that we take on!

It's 2 weeks old contract, we always had dedicated server so we never had this problem but seems that with Cloud servers yes you need to contact them and it's contract related so if you just add server to the same contract you don't have to contact them but if you open a new contract with new servers yes you will need to contact them
 
Solved, you need to contact them, even if you open it in the firewall they blocked it and actually I can send email without open it in the firewall.
I can confirm this with Ionos dedicated cloud servers. If you are using your own nameservers and sending mail through your Plesk server hostname, you MUST call and have them unblock port 25 OUTGOING. The Ionos cloud server panel firewall gives you control ONLY over incoming ports, not outgoing. This had me banging my head against the desk for 2 days before I found this thread. Even the Ionos Level 1 support doesn't seem to know this. I had to force it to Level 2 support and they acknowledged this fact and opened port 25 outgoing. All works well now. I have had many dedicated hardware servers with them over many years but this is my first dedicated cloud server. Lots and lots of landmines if you are not using their nameservers or mailservers when you use their cloud hosting and NO documentation or KB on things like this.
 
Cool! It's good that you can now achieve what you wanted.

It's quite odd though, as we've never had to contact IONOS about "...Open Cloud Server Ports That Are Still Blocked By IONOS..." If yours is a relatively new IONOS contract, then maybe... it's a recent IONOS 'rule addition' but only for new server placements? We'll double check on the next one that we take on!

If you are using your own nameservers and sending mail through your Plesk server hostname, you MUST call and have them unblock port 25 OUTGOING. The Ionos cloud server panel firewall gives you control ONLY over incoming ports, not outgoing. This had me banging my head against the desk for 2 days before I found this thread. Even the Ionos Level 1 support doesn't seem to know this. I had to force it to Level 2 support and they acknowledged this fact and opened port 25 outgoing.
 
@StormFiber You've copy-pasted almost all of the previous post, that was made by @KirkM but not added anything else to make that worthwhile.
Was that just a posting error?

FWIW @KirkM in relation to your own original and helpful informative post, you're right to point out the obvious bit that wan't mentioned (in detail) prior to your post. This bit: "The Ionos cloud server panel firewall gives you control ONLY over incoming ports, not outgoing" (sic) That missing detail plus post #10 made by @Seba which identifies the 'unseen' factor i.e. The contract that you have with IONOS, looks like it gives the complete answer to this thread.

We've already posted that we've never, ever had port 25 blocked (meaning incoming by us and outgoing by IONOS) yet we use IONOS Cloud Servers and IONOS nameservers / IONOS DNS (which you've referenced as 'your own') We're asuming that any non-Plesk nameservers / DNS is what you meant by that reference?. That setup works perfectly well with Plesk Obsidian for us and presumably, anybody else with IONOS cloud servers, if, their config is correct! (See previous paragraph).
 
which you've referenced as 'your own'
I probably should have said "custom nameservers" to be more clear.
We're asuming that any non-Plesk nameservers / DNS is what you meant by that reference?
No, it is not "non-Plesk nameservers, I use Plesk to handle all of my DNS and nameserver setup. It is non-IONOS nameservers and DNS management
 
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@KirkM :) Ahhhh yes. Makes much more sense in context now. Thank you. Must be another factor as to why we've never had the blocked port 25 issue.

Back when is was 1and1, using the DNS setup that was provided with their cloud servers, was still sketchy and far from being 100% acceptable. Once it changed its name to IONOS and things were overhauled / relaunched, then using their DNS package improved massively. It's still not 100% compatible with Plesk e.g. Plesk's "DNSSEC for Plesk" package will not work, if you're only using IONOS DNS (Edit: on an IONOS Cloud server...) but it's much better than it was.
 
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I have been with 1&1 (now Ionos) for literally decades but always had a dedicated hardware box (since cloud servers didn't exist when I started doing this). I have always created my own custom nameservers and specific DNS templates for some of my specialized applications. I didn't really know anything else but complete autonomy in having my server so I was a little lost with some of the differences when I got this new cloud dedicated server. I was doing everything the way I had always done but didn't initially realize that even as a dedicated server, if you are cloud serving, you are part of their bigger matrix and they have their own controls over you to some extent. I kind of like the separate box better in some ways, but cloud servers give a lot more bang for the buck so old dog needs to learn new trick. As long as I can completely control the server core, nameservers, DNS and perform my preferred server hardening, I should be good. I do use DNSSEC for Plesk and so far I am impressed with the ease of use through the panel. That and a few other things make it very much worth it to me to do the little bit of work and add the two extra IP addresses to set up custom nameservers. YMMV, of course.
 
For people like me who are still having this issue in 2022: Before making any of these configuration changes, I strongly recommend that you call your service provider. I'm at IONOS and I had to call them to unblock port 25 on their side !

I spent hours looking for the problem in my VPS whitout any trace of solution. I opened ports 25 and 587 on my cloud panel, that was not enough. Call your provider you will save time!
 
And now in 2023 they've changed their VPS infrastructure and even the 1st line Server team don't have a clue what they need to do...

just been on a call for 2 hours and the engineer is struggling to understand the issue or which port to open where...
 
And now in 2023 they've changed their VPS infrastructure and even the 1st line Server team don't have a clue what they need to do...

just been on a call for 2 hours and the engineer is struggling to understand the issue or which port to open where...
Their offerings and prices are pretty good, but their Tech Support is HORRIBLE. I get cold sweats when I have an issue and am forced to call them.
 
Now, in 2024, I phoned ionos, got through in seconds, told the support engineer what I wanted, and he enabled port 25 outgoing straight away. It was working before I even hung up the phone. Perhaps you get a better class of engineer at the weekend.

Result :cool:
 
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