Level 2: Rookie

SMTP issues for Linux servers

I run an I.T business from home and have been using cable broadband since around 2004. I have Linux servers that are using as their SMTP outbound gateway - this has worked perfectly even when I went onto the NBN recently with a dynamic IP address.

I changed the service to be issued with a fixed IP address which was done almost instantly. Two issues prevented my using for the outbound SMTP server after this change to a static IP: 1. The IP issued to me was blocked by the SpamHaus PBL service - this was fixed by simply going to their website and un-blocking the IP, 2. continues to issue the following error in spite of the unblocking:

 mailer=relay, pri=274954, [], dsn=5.0.0, stat=Service unavailable


This is common with a few scenarios (one as described above) but upon examining the failed returned e-mails at my end, it is insisting that I authenticate to be allowed to send. I _do_ understand this but given it wasn't an issue on the dynamic IP address, why is it now an issue for me with a fixed IP? One would think the opposite of this to be more logical.


In any event I don't use the Microsoft mailbox BigPond have given me and I don't use POP/IMAP outbound either. All of my e-mail is handled internally but I much prefer, as I install for customers, for the outbound SMTP server to be set to that of the ISP.

I tried to remedy this yesterday and after spending considerable time to speak to a higher level tech, to whom I told him I had just discovered and unblocked the SpamHause issue, I got off the phone.

But today it appears there is still no ability to send from my setup through the server which I have done without issue since 2004.

Are you able to offer guidance as to whom I can directly contact at NBN/BigPond/Telstra to get this sorted. The tech I spoke to believed the SMTP server would not block the service for outbound SMTP just because I had changed to a fixed IP address.


Hope you can point me in the right direction as waiting a long time on the phone is not an option at the moment.

Many thanks in advance and Happy New Year to you and the staff for 2016.

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Level 23: Superhero

Re: SMTP issues for Linux servers

Hello, Unless things have changed, Telstra still does not support Linux. 

As an ex-Linux user, your best resource is  and go to the Linux forum.

There are almost always very clued up Linux folk there.


Telstra's NBN support phone number is 1800 TFIBRE


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Level 2: Rookie

Re: SMTP issues for Linux servers

Thanks ProfessorPhone - this is a BigPond issue as it is blocking outbound e-mail from my fixed IP. I can bypass this simply by not using their SMTP server (and perhaps eventually setup an SPF record with my DNS registrar) but there is no logic in why it worked for 11 years via cable (from the same kind of Linux server setup at my end), then worked these past few weeks on their dynamic IP address. As soon as I went fixed IP, BigPond SMTP is refusing my connection and insisting I user auth (SMTP Auth - which I can also do), but there is no reason for this to stop now.
I will have to spend ages on the phone again on Monday until I get put through to someone who actually understands what I am talking about....... and tell me I will be charged if it is my fault/end, which it isn't.

Thanks again and Happy New Year. 

Level 2: Rookie

Re: SMTP issues for Linux servers - NOT RESOLVED BUT DO HAVE A WORK-AROUND

Well after spending over another half an hour talking to Telstra I was finally put through to the Platinum support and the guy there said they only support Mac and MS, not Linux..... which is just rediculous regardless of how you spin it.

So they cannot help me even though the dynamic cable and dynamic NBN IPs had no block on outbound SMTP through and it has only become blocked after I had the new fixed IP. The only thing that changed in my/their setup was the fixed IP adddress.

So this is pretty useless and it will now make me think twice about using Telstra as an NBN service for all my customers based on the SMTP outbound blocking issue.

Now I am force to setup SFP in the DNS registrar - lucky I know how to do that.....


Level 2: Rookie

Re: SMTP issues for Linux servers - NOT RESOLVED BUT DO HAVE A WORK-AROUND

Hi All - after changing the IP address from Dynamic to Static, was showing "Connection Refused" on the Linux Sendmail server.
Telstra offered to change the fixed IP again to see if this fixed the issue.
It didn't fix the issue with a second static IP address and while I was on the dynamic IP for a day SMTP outbound e-mail via did work - so this issue is something with their fixed IP address allocation and possibly trusting 'relay' through it.

I have repeatedly told them using is the same for any SMTP outbound, regardless of whether I have a Linux e-mail server or a Microsoft Exchange server.

Solution is to ensure your DNS (Reverse DNS and spf) is setup and then bypass simply by delivering directly via port 25 to the Internet.


My actual solution now is to use my other Internet connection for outbound which will go through tpg.

Also to note, the second static IP was also listed by SpamHaus but now I review this I believe this is more a SpamHaus thing locking down anything they perceive as a dynamcally assigned range.


Level 7: Deputy Inspector

Re: SMTP issues for Linux servers

Solution I found several years ago was to set Google and/or Yahoo to collect and send our Bigpond emails.


Gradually worked through all those on our mail list to make sure they  changed their addresses to our Google&/Yahoo.   




Problem once, when passwords reset self forgot to change password on Googe/Yahoo,  was quickly fixed.



Push for everyone to use MS-W continues,  while for self change to linux fixed 90% my problems,  so whatever happens with next Telstra/Bigpond email changes, they  unlikely to be problem. 




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