As a spam mitigation measure, some of the broadband providers are starting to block port 25 for outgoing mail (to keep all those unpatched, zombified windows boxes from flooding the world with more junkmail). Port 25 blocking is old news in some parts of the U.S., but it just hit SBC Customers in California. (I spent a half-hour this evening sorting out why my wife can't send email. Once we had it narrowed down to "hey, I can ping the host, but I can't telnet to port 25" the clue-light went on.)

Here are the details for SBC Global DSL, including workarounds. If you have a different DSL provider, now might be a good time to see what their plans are, so you're not caught by surprise. And if you have a provider you can ssh into, and you aren't tunneling your email through ssh, well, shame on you.

  • Comment on [OT] Heads-up on broadband providers blocking port 25

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Re: [OT] Heads-up on broadband providers blocking port 25
by xdg (Monsignor) on Mar 01, 2005 at 13:04 UTC

    Since we're clearly marked off topic, I'll put in a plug for Speakeasy DSL, which I've used for about 5 years now. Not only do they have great quality (uptime, service), they actually understand that users might want to run servers on an ADSL line and have Terms of Service that are compatible. Want to have reverse DNS mapping to your static IP? They even do that.

    If you're inclined to give them a try (in a way that gets me a referral credit), please use this URL: Otherwise, use the one above.


    Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.

      Seconding the Speakeasy recommendation. I dropped them for (*blech*) Comcast only because they weren't able to get me anything faster than IDSL and I needed more bandwidth than that. The support people at least have heard of OSen other than Wintendo and were pretty helpful and timely. If only they weren't dependent on the whims of the RBOC to provide ADSL through fiber to the SLC . . .

Re: [OT] Heads-up on broadband providers blocking port 25
by KeighleHawk (Scribe) on Mar 09, 2005 at 00:21 UTC
    Another option to consider is looking into the low end "business class" service. Some smart feller somewhere started catching a clue cloud and started offering lower cost service under the "business" label. That means things like static IP's, mail and web servers, etc. actually ARE supported functions.

    Plus, when service goes down, you can call up and start screaming about "lost business" and people get hopping.

    They may or may not be able to help much with personal setups but at least they do the part they are supposed to do and then get the hell out of your way.

    In general, the few I looked at (I settled on Cox Cable because I am not much impressed with DSL providers in general and Cox was the only cable option) tend to charge twice the going rate of the standard, residential (aka entertainment) service for the low end business service. Verizon actually has several low end service offerings. Just be sure to check the actual feature set since each ISP is somewhat different on exactly what they do and don't support.