SurferTim
Posts: 1800
Joined: Sat Sep 14, 2013 9:27 am
Location: Miramar Beach, Florida

Re: Can't send an email from this tutorial!

Fri Sep 15, 2017 10:34 pm

Have you considered getting a static commercial IP from your ISP? It isn't free, but it would allow you to get your email server IP off the blacklist.

Dalmango
Posts: 46
Joined: Sat Aug 05, 2017 5:21 pm

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 10:54 am

My plan is to do that if I could get my own raspberry pi server up and running, and to do this when I move house which is likely to be in a few months.

However I think that I'm only going to get blacklisted again as I think the problem is that it's doing a reverse lookup and my domain ip address is not matching where my current domain is being hosted.

SurferTim
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Location: Miramar Beach, Florida

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 11:25 am

It doesn't matter about your domain IP. According to the message in your log, it is your email server's IP that is blacklisted.

Dalmango
Posts: 46
Joined: Sat Aug 05, 2017 5:21 pm

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 5:33 pm

Thanks Tim, there's something up because this has only happened since playing around with postfix.

I really think it's from sending an email and the recipient client doing a reverse lookup as I've watched countless tutorials and a way of filetering spam was to reverse look up and see if the email being sent ip address matched the domain registration ip address. It's 100% something since messing around with postfix as my ip was fine at first.

Thanks again for your input.

SurferTim
Posts: 1800
Joined: Sat Sep 14, 2013 9:27 am
Location: Miramar Beach, Florida

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 6:20 pm

Dalmango wrote:
Sat Sep 16, 2017 5:33 pm
Thanks Tim, there's something up because this has only happened since playing around with postfix.

I really think it's from sending an email and the recipient client doing a reverse lookup as I've watched countless tutorials and a way of filetering spam was to reverse look up and see if the email being sent ip address matched the domain registration ip address. It's 100% something since messing around with postfix as my ip was fine at first.
What do you mean "...as my ip was fine at first"?
What do you mean "...there's something up because this has only happened since playing around with postfix. "?

Many email servers do not have the same IP as the domain IP, and some not even the mx record. My ISP uses two servers. One sends and one receives. The sender is not the mx record.

Do you have a static IP where your email server is? If not, and you get a dynamic IP, that is most likely the problem. BTW, I ran my own email servers for years. This is not my first rodeo.

hortimech
Posts: 444
Joined: Wed Apr 08, 2015 5:52 pm

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 6:48 pm

Do you a fixed external IP ?
Your domain records need to be pointed at a fixed IP.
If you have been given a dynamic IP by your ISP, then this is never going to work.
You can relay your domains outgoing email through your ISP's mail servers, but how do you get any replies ? Your domains MX record will have an IP record, but what if this has changed in the mean time ?

Dalmango
Posts: 46
Joined: Sat Aug 05, 2017 5:21 pm

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 6:58 pm

Thanks Tim please see my responses in red.

What do you mean "...as my ip was fine at first"? Was not blacklisted
What do you mean "...there's something up because this has only happened since playing around with postfix. "? My ip was not blacklisted until trying to send emails from postfix

Many email servers do not have the same IP as the domain IP, and some not even the mx record. My ISP uses two servers. One sends and one receives. The sender is not the mx record.

Do you have a static IP where your email server is? If not, and you get a dynamic IP, that is most likely the problem. BTW, I ran my own email servers for years. This is not my first rodeo. I appreciate that, yes I do have a dynamic IP adress as discussed earlier; however at this moment in time before investing in a fixed ip address I'm just playing around with my dynamic address and getting it to work with this.
[/quote]

Thanks again for your input.

SurferTim
Posts: 1800
Joined: Sat Sep 14, 2013 9:27 am
Location: Miramar Beach, Florida

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 7:25 pm

OH! So what email server software did you use before postfix? Sendmail?

Dalmango
Posts: 46
Joined: Sat Aug 05, 2017 5:21 pm

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 8:34 pm

hortimech wrote:
Sat Sep 16, 2017 6:48 pm
Do you a fixed external IP ?
Your domain records need to be pointed at a fixed IP.
If you have been given a dynamic IP by your ISP, then this is never going to work.
You can relay your domains outgoing email through your ISP's mail servers, but how do you get any replies ? Your domains MX record will have an IP record, but what if this has changed in the mean time ?
Hi Hortimech, thank you for your input. Yes I am on a dynamic ip address, but my plan was to just try to see if I could get postfix up and running on my dynamic ip address as I plan to be moving house soon and if I can get this working then I'll invest in a fixed ip address.

I had earlier tried to relay my outgoing messages however I do not have an email account with my ISP so I'm not sure how I could ever relay an email with the ISP mail server.

Thanks again for your input.

Dalmango
Posts: 46
Joined: Sat Aug 05, 2017 5:21 pm

Re: Can't send an email from this tutorial!

Sat Sep 16, 2017 8:36 pm

SurferTim wrote:
Sat Sep 16, 2017 7:25 pm
OH! So what email server software did you use before postfix? Sendmail?
No Tim, as I'm sure you've grasped already I'm a complete noob, I have a Microsoft Exchange Server (didn't configure just part of my server package).
Enjoying learning all this, but there's quite a lot to it and it's consuming all my time lol.

Using the MX Toolbox it appears that my ip address is not even blacklisted https://mxtoolbox.com/blacklists.aspx

hortimech
Posts: 444
Joined: Wed Apr 08, 2015 5:52 pm

Re: Can't send an email from this tutorial!

Sun Sep 17, 2017 3:07 pm

You cannot use a dynamic IP for a mailserver, you need a a fixed IP and have the domains MX record pointing to this.

You can relay outgoing mail through another email server you have an account on (provided they allow this, gmail does for instance) but any replies would go to your account on the external email server. You could use something like getmail or fetchmail to bring the mail from there and deliver it to your internal email server, but you would have to use the same email domain as the external email server.

Just owning a domain is not enough, you must have a fixed IP and have the domain records point to this.
There is another gotcha, some ISPs will not allow you to use port 25.

Dalmango
Posts: 46
Joined: Sat Aug 05, 2017 5:21 pm

Re: Can't send an email from this tutorial!

Sun Sep 17, 2017 5:25 pm

Ok, thanks guys, sorry for my ignorance Tim, I thought it might be possible to refresh a dynamic ip regularly and using dns pointers to point back to the dynamic ip address. I've read an article on how to do this.

However the problem seems to be that the recipient's reverse lookup's nowadays is seeing the my email being sent from a partly setup email configuration (as I'm in the early stage of the telnet tutorial) from a dynamic ip address and it marks it as spam.

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DougieLawson
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Re: Can't send an email from this tutorial!

Sun Sep 17, 2017 5:55 pm

hortimech wrote:
Sun Sep 17, 2017 3:07 pm
You cannot use a dynamic IP for a mailserver, you need a a fixed IP and have the domains MX record pointing to this.
The OP is trying to send email, not receive it. No need for fixed IP or an MX record for that.

What the OP needs to do is trace the conversation with the mail server that's he/she is trying to use as the relay and that should give a reason why it's rejecting the email envelope and the payload.
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