General Postfix Knowledge Question..

Do I understand correctly that postfix, uses port 25 to send out all email from the server itself, plus all the domains created on the server?

And, it also uses Port 25 to listen for email that comes in from the internet in general for all the domains that reside on the server?

Thanks
Tom

Howdy,

Email servers (including Postfix) listen on port 25 for email.

When sending email, by default, those emails would need to go out on port 25 (since that’s the port most emails servers listen on).

-Eric

Hey Eric,

Thanks for taking time to reply. I know its a busy world and time is in short supply.

So, Since I am behind a blocked port 25, even though I can use an relay host such as sendgrid, mandrill, or dnsexit, to relay out and allow webmin to send email out, do those pass back into the server for receiving emails as well? or does the block just screw me all the way around?

I have been on google for days, and crashed firefox so many times. Seems like the information I am finding seems to send me in the wrong direction.
I have managed to get it to send email via at@t isp server, but that is logging in, and it has to show ever email sent as being from my isp email address. so none of the email users on the system can send anything unless it looks like me. that wont wont work. If i was going to do that, i would just give out my details and let every one log in and see everything.

The only thing i have noticed at this point, is if those relay services will allow mail to pass both ways… in and out of the server. or, if I could do something like linoid, and set up a cheap account and run postfix there as well, and have it relay for me. not sure I can figure that out from scratch on that end. and when trying to research some post said I would have to do it via a vpn Never used vpn so I am not sure i could manage.

Any advise would be appreciated.

Regards
Tom

Howdy,

Unfortunately, if your provider blocks port 25, there wouldn’t be a way for remote email servers to send email to you. There isn’t a way to tell a sending server that it needs to use an alternate port or route.

I don’t imagine you could use that same Linode to act as your server, could you?

Those Linode’s are pretty good servers, even the lower end ones, and that may be an easier option than trying to setup some sort of workaround to the issue you’re seeing.

-Eric

Hey Eric,

Thanks again,

Well, my whole reason for setting up at home was to get away from paying so much for my online crap. Paying way to much to play around. I dont need a lot of speed. so my dsl would surfice. but ATT will not budge on the issue unless I take business class service. again, higher price, and according to there website, business services are not available in my area.

Go figure,

So, If i change and run everything on the linode, there goes my price up. I didnt think 10 bucks a month would have been to bad if i could have resolved the issue and let it relay back in as well. oh well, not sure how there is so much spam out there if this is the case… looks like the ban on port 25 dont stop the spammers, but instead keeps the proper use of it all from being usable.

Thanks again for all of your information… I do appreciate the knowledge that others like you share.

Regards

Hey Eric,

Think it would be possible to continue to run the server here, and configure virtualmin / webmin and all to use post fix on a linode server offsite?

so that, the email server would then be offsite with the rest of the server items local here?

did that make sense?

Thanks
Tom

**** add on thought ****
I wouldnt mind moving one of the name servers to the linode as well.

Anyone know of an instructional anywhere that would help me with that?

Well, my whole reason for setting up at home was to get away from paying so much for my online crap. Paying way to much to play around. I dont need a lot of speed. so my dsl would surfice. but ATT will not budge on the issue unless I take business class service. again, higher price, and according to there website, business services are not available in my area.
You can find VPS for 5-6$/month with 0.5-1GB RAM what would be enough to play around. Cheapest plan on Linode is 1GB for 10$/month what should be enough to run even several websites with low traffic but still better than hosting at home.