44net

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3198 discussions

Re: [44net] SMTP port 25
by kb9mwr＠gmail.com 13 Aug '14

13 Aug '14

Actually what I said doesn't make any sense. I don't understand where the problem is. I'd still like to hear from anyone running a SMTP server on Linux, not NOS.

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Re: [44net] SMTP port 25
by kb9mwr＠gmail.com 13 Aug '14

13 Aug '14

I was going to run a pipermail email list on a 44 IP. While I am sure I can get it to work fine between other 44 hosts, my guess is that it will see little use if I can't make it work like any other host on the wide internet. The latest problem again is with outside connectivity. There seems to be some sort of TTL issue going on. My network /host isn't always reachable from the internet. And it seems to depend on who you are using for internet. My host: 44.92.21.35 Seems to work fine from a time warner cable connection in Green Bay. But other people report not being able to reach it. Looking at other 44net hosts connected to the internet: pinging 44.88.0.9 - Fine pinging 44.4.92.50 yes but with packet loss So it turns out a lot of my SMTP headaches track back to this bigger problem.

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Re: [44net] SMTP port 25
by lleachii＠aol.com 13 Aug '14

13 Aug '14

- Are you willing to establish an email server and be willing to maintain it? - Who would be responsible for maintaining the accounts? - Do you have a privacy policy in place? - What is your ISP's bandwidth limit? - Do you have the facilities to backup and store emails for all users? - The same DNS entries would be required, and the ampr.org domain (or subdomain) would have to be the only one used. -KB3VWG > At the very least shouldn't AMPRnet folks be able to send and receive > email from other AMPRnet stations? I'd think that would be a good > first step for dealing with EMail. A bit easier and safer than > dealing with the whole Internet. > Bill

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Re: [44net] SMTP port 25
by lleachii＠aol.com 12 Aug '14

12 Aug '14

Steve, I have ran mail servers, but I do not currently run one on AMPRNet; my last attempt was to setup a home server was an IPv6-only server for the purposes of passing a certification exam. There are many reasons for not maintaining it (some of which may be why you're having issues, hope this helps): - The domain you're using for email must have an MX record - That MX record must point to a valid A Record (it doesn't have to be the same domain) - Your mail server must be configured with the hostname name noted in the A Record - The IP noted in the A record must have a PTR record that returns the same hostname in the A Record (this can only be done by one of our friendly Brians, this has to be done in 44.in-addr.arpa) also make sure that - you have configured the SMTP server to receive email for the domain in which you created a global MX record entry - make sure that email account exists on the server - if it is multi-homed, make sure the gateway/default route is over 44NET While mail servers should work with the first two, many ISPs configure their servers only to "talk" with mail servers who also have the PTR record in place. -Lynwood KB3VWG

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Re: [44net] SMTP port 25
by kb9mwr＠gmail.com 12 Aug '14

12 Aug '14

Thanks for the explanation Tim. I haven't messed with running a mail server since 1999 so a lot has apparently changed, and I am a bit concerned about doing it right. Presently I am trying trying exim on a CentOS platform. It seems to send out mail just fine, but when it comes to answering someone else connecting to it from the general internet that is were I apparently don't have something configured right yet. Anyone care to create a nice write up :-)

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Re: [44net] SMTP port 25
by William Lewis 12 Aug '14

12 Aug '14

I found that Comcast only blocks "Residential" subscribers from port 25. The minute I upgraded to a "Commercial" account, all restrictions were removed. The best part was that for a commercial account with one dedicated IP address, it was cheaper than the residential service was. Not sure this approach will work for all though. Bill KG6BAJ At 05:39 PM 08/11/14, you wrote: >(Please trim inclusions from previous messages) >_______________________________________________ >Is anyone running a SMTP server on their gateway? > >Most ISP's block port 25 outgoing, the problem I am seeing.

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Re: [44net] SMTP port 25
by Jason Begley 12 Aug '14

12 Aug '14

What ISP are you using. Most do block outbound 25. ATT will unblock if you get the right person on the phone. KY9J -------- Original message -------- From: kb9mwr(a)gmail.com Date: 08/11/2014 8:50 PM (GMT-05:00) To: 44net(a)hamradio.ucsd.edu Subject: Re: [44net] SMTP port 25 (Please trim inclusions from previous messages) _______________________________________________ Actually what I said doesn't make any sense. I don't understand where the problem is. I'd still like to hear from anyone running a SMTP server on Linux, not NOS. _________________________________________ 44Net mailing list 44Net(a)hamradio.ucsd.edu http://hamradio.ucsd.edu/mailman/listinfo/44net

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Re: [44net] SMTP port 25
by kb9mwr＠gmail.com 12 Aug '14

12 Aug '14

Turns out you have to specify the interface address for sendmail to respond to, 127.0.0.1 is default so that is why that always worked. I never ran into that one before, That explains this weirdness.. Two boxes on my local LAN with no iptables software firewalls or hardware firewalls between them, and selinux off on both: [root@kb9mwr ~]# ifconfig eth0 eth0 Link encap:Ethernet HWaddr 00:21:85:9C:60:42 inet addr:192.168.1.100 Bcast:192.168.255.255 Mask:255.255.0.0 inet6 addr: fe80::221:85ff:fe9c:6042/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:5421757 errors:0 dropped:0 overruns:0 frame:0 TX packets:4042659 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1012253009 (965.3 MiB) TX bytes:2506193160 (2.3 GiB) Interrupt:58 Base address:0xe000 [root@kb9mwr ~]# telnet localhost 25 Trying 127.0.0.1... Connected to localhost.localdomain (127.0.0.1). Escape character is '^]'. 220 kb9mwr.host.org ESMTP Sendmail 8.13.8/8.13.8; Mon, 11 Aug 2014 19:59:42 -0500 ^] telnet> root@pbx:~ $ telnet 192.168.1.100 25 Trying 192.168.1.100... telnet: connect to address 192.168.1.100: Connection refused telnet: Unable to connect to remote host: Connection refused I was well aware that most ISP's block that port but was really stumped as to why to PC's on the same network could not talk to each other on that port yet could on all other ports. You learn something new every day.

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SMTP port 25
by kb9mwr＠gmail.com 12 Aug '14

12 Aug '14

Is anyone running a SMTP server on their gateway? Most ISP's block port 25 outgoing, the problem I am seeing. I see a email handshake come in and forward over the wireless LAN, But when it comes from a non 44 IP is tries to reply using my assigned ISP provided IP and obviously that doesn't work. So is there some way with IP tables or something else to set and advanced IP rule where is it's a destination on port 25 to route thru amprgw.sysnet.ucsd.edu using my 44 address?

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Re: [44net] 44Net Digest, Vol 3, Issue 131
by Ernest.Tse＠Pacswitch 12 Aug '14

12 Aug '14

An embedded and charset-unspecified text was scrubbed... Name: not available URL: <http://hamradio.ucsd.edu/mailman/private/44net/attachments/20140812/5319c5f…>

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