Comments on: Comcast Cosed my Outbound Port 25 Yesterday http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/ Utterly random, incoherent and disjointed rants and ramblings... Thu, 20 Nov 2008 11:19:12 +0000 http://wordpress.org/?v=2.0.5 by: vacri http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8971 Tue, 06 May 2008 03:17:19 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8971 take a printout of your Mr Rooter and Mr 126 times along with you to management. Point out that this one event cost 3 hours of your wages... and then point out that replacing the modem 3 times the previous year cost more of your wages, downtime, any other charges you can think of, all on bad 'residential' advice. Point out also that the time you spend working around the blocks put on a residential service effectively costs the company as well, time that could be better spent <strike>chatting to the receptionist</strike> working diligently for increased profit margins. take a printout of your Mr Rooter and Mr 126 times along with you to management. Point out that this one event cost 3 hours of your wages… and then point out that replacing the modem 3 times the previous year cost more of your wages, downtime, any other charges you can think of, all on bad ‘residential’ advice. Point out also that the time you spend working around the blocks put on a residential service effectively costs the company as well, time that could be better spent chatting to the receptionist working diligently for increased profit margins.

]]> by: Luke Maciak http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8964 Mon, 05 May 2008 01:51:18 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8964 Yeah, but that's what happens in small companies - the "why do we need the expensive business plan if we could buy two residential ones for the same price" factor comes into play. :P Yeah, but that’s what happens in small companies - the “why do we need the expensive business plan if we could buy two residential ones for the same price” factor comes into play. P

]]> by: vacri http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8960 Mon, 05 May 2008 00:55:44 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8960 [quote comment="8937"][quote post="2423"]er… I assume your company uses a professional connection.[/quote] Actually, we seem to be on a residential circuit - go figure. I'm assuming it got set up like that, because it dirt cheep at the time. :( Oh well, I guess this is a good argument to present to the big boss in explaining to him why the extra expense is actually worth it.[/quote] Just had one of those jaw-drop moments. Running a business on a residential connection is insane. Business contracts come with better SLAs, better response times, and easier access to assistance. Depending on your SLA, you may even have a right to compensation if your business suffers because of a loss of connection due to avoidable actions at the ISP end. If a morning without email sends your company into a panic, then you shouldn't be on a residential connection. That being said, I've heard an argument for SMBs having two residential connections with different ISPs over different paths, as some outages affect both business and residential users identically and sometimes the business connections are insanely priced. Basically you use one residential line to cover for outages in the other. Luke Maciak said:

er… I assume your company uses a professional connection.

Actually, we seem to be on a residential circuit - go figure. I’m assuming it got set up like that, because it dirt cheep at the time. (

Oh well, I guess this is a good argument to present to the big boss in explaining to him why the extra expense is actually worth it.

Just had one of those jaw-drop moments. Running a business on a residential connection is insane. Business contracts come with better SLAs, better response times, and easier access to assistance. Depending on your SLA, you may even have a right to compensation if your business suffers because of a loss of connection due to avoidable actions at the ISP end. If a morning without email sends your company into a panic, then you shouldn’t be on a residential connection.

That being said, I’ve heard an argument for SMBs having two residential connections with different ISPs over different paths, as some outages affect both business and residential users identically and sometimes the business connections are insanely priced. Basically you use one residential line to cover for outages in the other.

]]> by: Luke Maciak http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8937 Fri, 02 May 2008 13:39:11 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8937 [quote post="2423"]er… I assume your company uses a professional connection.[/quote] Actually, we seem to be on a residential circuit - go figure. I'm assuming it got set up like that, because it dirt cheep at the time. :( Oh well, I guess this is a good argument to present to the big boss in explaining to him why the extra expense is actually worth it. [quote post="2423"]Also, a protip you probably already know: my favorite tool for diagnosing smtp-troubles is ‘telnet’.[/quote] Yep, that's what I was doing. Actually, I have a sheet with the list of relevant POP and SMTP commands hanging in my cube just for the times like this. :)

er… I assume your company uses a professional connection.

Actually, we seem to be on a residential circuit - go figure. I’m assuming it got set up like that, because it dirt cheep at the time. (

Oh well, I guess this is a good argument to present to the big boss in explaining to him why the extra expense is actually worth it.

Also, a protip you probably already know: my favorite tool for diagnosing smtp-troubles is ‘telnet’.

Yep, that’s what I was doing. Actually, I have a sheet with the list of relevant POP and SMTP commands hanging in my cube just for the times like this. )

]]> by: Tino http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8936 Fri, 02 May 2008 12:34:13 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8936 I agree that it makes no sense for an ISP to without prior notice suddenly block ports on a company connection. However, I don't think blocking outgoing port 25 is a short-term knee jerk thing. It really makes it impossible for spammers to use hacked local computers as spam relays. If outgoing port 25 traffic is blocked there really is no way to directly contact most of the email servers on the Internet, since they all listen on port 25. The spammer would have to set the hacked computer to go through another relay on another port -- and if so, the first relay is useless as it does not expand the bandwidth. Also, a protip you probably already know: my favorite tool for diagnosing smtp-troubles is 'telnet'. Simply doing telnet smtp.offsite.example.com 25 and run the smtp conversation manually to inject an email have helped me find the source of several problems in the past. I agree that it makes no sense for an ISP to without prior notice suddenly block ports on a company connection.

However, I don’t think blocking outgoing port 25 is a short-term knee jerk thing. It really makes it impossible for spammers to use hacked local computers as spam relays. If outgoing port 25 traffic is blocked there really is no way to directly contact most of the email servers on the Internet, since they all listen on port 25. The spammer would have to set the hacked computer to go through another relay on another port — and if so, the first relay is useless as it does not expand the bandwidth.

Also, a protip you probably already know: my favorite tool for diagnosing smtp-troubles is ‘telnet’. Simply doing
telnet smtp.offsite.example.com 25
and run the smtp conversation manually to inject an email have helped me find the source of several problems in the past.

]]> by: vacri http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8934 Fri, 02 May 2008 04:07:13 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8934 Furthermore, if it is a professional connection, why did they not warn you in advance of changes that may affect business? Shutting off an industry standard port surely falls under that category. Furthermore, if it is a professional connection, why did they not warn you in advance of changes that may affect business? Shutting off an industry standard port surely falls under that category.

]]> by: vacri http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8933 Fri, 02 May 2008 04:06:07 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8933 er... I assume your company uses a professional connection. Why on earth are they blocking ports on a professional connection? The implication of a professional connection being that there's a sysadmin of some stripe administering it? er… I assume your company uses a professional connection. Why on earth are they blocking ports on a professional connection? The implication of a professional connection being that there’s a sysadmin of some stripe administering it?

]]> by: Travis McCrea http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8932 Fri, 02 May 2008 00:23:01 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8932 I think its very innovative though, to use twitter. If I was running a company I would use all means like that, myspace the works... that way everyone can stay connected. I think its very innovative though, to use twitter.

If I was running a company I would use all means like that, myspace the works… that way everyone can stay connected.

]]> by: Luke Maciak http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8931 Thu, 01 May 2008 23:29:21 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8931 I'm sure that is not his only responsibility. But yeah, being the Twitter spokesperson for a company wouldn't be a bad job. :P I’m sure that is not his only responsibility. But yeah, being the Twitter spokesperson for a company wouldn’t be a bad job. P

]]> by: Travis McCrea http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8930 Thu, 01 May 2008 22:29:12 +0000 http://www.terminally-incoherent.com/blog/2008/05/01/comcast-cosed-my-outbound-port-25-yesterday/#comment-8930 God I want to be a guy being paid to use twitter all day. God I want to be a guy being paid to use twitter all day.

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