On 21 Nov 2005 at 16:06, Rob Brenart wrote about
"Re: [exim] smarthost relay problems":
| Fred Viles wrote:
| >
| > What machine is this exim running on? Is it connected to the
| > Internet by an ISP that blocks outbound port 25?
| >
| >
| It's on my local server sitting under my desk... connected through SBC
| DSL.. I didn't think port 25 was blocked, but I could be wrong
I think SBC has recently (for some value of "recent") started
instituting port 25 blocking. Demonstrably, they are doing it in
your case. Your smarthost definitely is listening on port 25, I can
connect to it just fine.
I have no idea whether you can get SBC to remove the block for you.
If you have dynamic IP, almost certainly not. If you have static IP,
it may be worth a try.
Port 25 blocking (or worse, transparent proxying) is becoming very
common these days, thanks to all the worms that turn PCs into spam
zombies. Any mail server that wants to support relaying for external
clients pretty much has to support connections on some other port.
That's one of the things port 587 (the MSA, "Mail Submission Agent"
port) is good for.
- Fred