Tracerouting mail.escuelaelectronica.org (domain hosted elsewhere.. I know the owner)




telnet to port 25

telnet mail.escuelaelectronica.org 25
Trying 72.9.247.50...
telnet: connect to address 72.9.247.50: No route to host

Could very well be your ISP. A lot of them don't allow outgoing traffic on port 25; this prevents machines from being used as spam zombies, or of actively spamming. This is sometimes even true of ISPs that should really allow this sort of thing.

Huh... thirty years ago, who would have believed that "spam zombie" would become a legitimate computer engineering term?

Quote: Original post by Sneftel
Could very well be your ISP. A lot of them don't allow outgoing traffic on port 25; this prevents machines from being used as spam zombies, or of actively spamming. This is sometimes even true of ISPs that should really allow this sort of thing.

Huh... thirty years ago, who would have believed that "spam zombie" would become a legitimate computer engineering term?

It's not my ISP. I have no problem sending mail from my computer :P.

As I've mentioned before, this is on a virtual dedicated server machine. Not my own.

Quote: Original post by Maega
As I've mentioned before, this is on a virtual dedicated server machine. Not my own.

And the ISP of this server may not allow it. ("ISP", in this case, can mean either the server facility or its bandwidth provider, though the former is much more likely.) All the signs are there: you can get ICMP through to the server, but you can't route to port 25, including through telnet, and you don't have any trouble with loopback on port 25. That strongly indicates that a router somewhere is refusing to route outgoing TCP/25 packets. I'm guessing that you won't have any problems finding a route if you try telnetting to other ports.

Quote: Original post by Sneftel

Quote: Original post by Maega
As I've mentioned before, this is on a virtual dedicated server machine. Not my own.

And the ISP of this server may not allow it. ("ISP", in this case, can mean either the server facility or its bandwidth provider, though the former is much more likely.) All the signs are there: you can get ICMP through to the server, but you can't route to port 25, including through telnet, and you don't have any trouble with loopback on port 25. That strongly indicates that a router somewhere is refusing to route outgoing TCP/25 packets. I'm guessing that you won't have any problems finding a route if you try telnetting to other ports.

Ah.. it appears you seem to be correct. The FAQ of the server provider mentions they have a relay server and ONLY says to use that unless you set up your own mail server.

I guess that isn't exactly true :D.

I tried telneting to 110 (POP3) and it let me through without a problem

I'll have to ask them what's up.

As I suggested before, the hosting provider have a policy of only allowing outbound relaying via THEIR relay.

Presumably this is so that they can keep tabs on what their customers are sending more easily, and detect spam, viruses or other undesirable content.

This is an excellent thing and you should be pleased (Unless you are a spammer of course).

Simply change Qmail's configuration so that it sends all email to this relay as a "Smart host" or similar.

Mark