Mark's Blog A developers point of view

HowTo: Run a mailserver, even if your ISP blocks SMTP port 25

After some hard work we have finally gone beta with our service: RerouteMAIL. A service with which you can easily run a mailserver even if your ISP actively blocks port 25.

A while ago I posted about some wild idea's where you could go around the SMTP block of your ISP by running your mail through another (non blocked) mailserver and forward it to your mailserver which is running on a different port. Today, we go beta with a service which makes this possible for everyone!

The road from 'Proof of Concept' to 'Finished Product' was, as always,  a bit longer than expected. First of all I switched from developing in PHP to Django (to expand my knowledge) and secondly, there are some pitfalls when you want to make this kind of service for more people than just yourself.

For the people who don't know what the fuzz is all about, a short rundown. There are ISP's in the world which believe that there are a lot of people who don't know what they are doing. So when those people run a mailserver chances are rather large that they don't configure their mailserver correctly, and they become an open-relay and thus, open for spammers to be used as spamming machine.

Although these ISP's are in their right to do so, we believe the clients (and especially the business clients) should have the chance to be able to run a mailserver if they completely understand the risks.

By default (and according to everyone and everything on the internet) a mailserver listens on port 25 for incoming mail messages. Because this is the default, ISP's block this port (incoming and/or outgoing).

Fortunately we have thought up a way around the ISP's who are actively blocking port 25.

As a lot of people (mostly unix administrators) know, you can run a mailserver on a different port than port 25, say port 26. However, the email world does not know this. So when a mailserver (for example the google mailserver) wants to mail to you, it tries to connect to port 25. And so you have to find a way to let the other mailserver think you are on port 26. But this can't be done easily and without your ISP.

It can be done via our new service: RerouteMAIL. The trick is that we listen on port 25. And then relay the incoming message to your mailserver running on port 26!

And the best part is, we have a fee free version which everyone can use, a hassle free registration, and no questions asked.

If you are interested or curious please have a look at: www.reroutemail.com or leave a comment on this blog!

The money problem with friend-groups: “Nah… I’ll pay! Pay me back later!”

You might recognise the problem. You have a close friend group and you do lots of things together. So when you go out,  or go to the movies you decide that you'll pay something, and the others pay other stuff and you dont realy worry about the money. They are your friends, and you trust everyone, so, no biggy.

Now although this is true, the problem lies where you can't keep track of what you owe who, or who owes you what. And although you know it's okay, it just doesn't feel right. Especially when it concerns larger amounts. For example, you go on vacation as a group. Decide that everyone will pay amount X as a money stash for group activities. But you know it is a matter of time before the plan becomes a bust. Eventually someone forgot his card and could not make a withdrawl. The account was empty sooner than expected. Etc. etc. In the end person X has deposited €400 person Y €600 and peson z only €200 because of whatever reason.

Now I have, on multiple occasions, decided to make a nice little Excel sheet which can handle these kind of problems. You enter the money you have spent (its a friend case so you trust everyone supplies accurate numbers) of each of the members, and it calculates neatly what the average amount spent is, and you can see who owes what to whom. Further, if person Z afterwards gave person X some money for something else, it is handy that these numbers can be specified too. So it will always reflect who has already settled his debt and who hasn't. The biggest problem is you have to manually keep track of changes. If someone pays somebody (partially or full), and didnt notify me, I can't keep track of the changes. And so it is a matter of time before it is not accurate anymore so you can't rely on it.

Because I (we) have these problems. I'd think I'm not the only one! So I think about making some simple application which can handle these kinds of troubles. Attach a mail service to it so people can easyly be reminded of his debts or request for information. Combine this with some type of grouping of friends and you have a centralised application to handle all current and future money oweing problems without worrying about who paid who (or didnt).