[svlug] ISP blocks port 25

[David Rosenstrauch]

Skip Evans wrote:
> Hey all,
> 
> I just switched my home ISP from Qwest to Bresnan 
> on a cable modem, and also discovered they block 
> port 25 on their home accounts so I am unable to 
> connect to my SMTP server here in the office on 
> port 25 to receive mail.
> 
> What is the most common workaround for this? Do I 
> just move the mail server to a different port?
> 
> Thanks!
> Skip


Do they block the OpenVPN port?  (UDP 1194)  If not, then you can do 
what I do:

Set up the OpenVPN daemon on your box.  Then you can OpenVPN in to your 
box, which will then let you access port 25 on the box via the openVPN 
connection.

I.e., I OpenVPN in to my server, which sets up my work machine with an 
additional interface (tun0) with an IP address on the VPN (10.1.0.2).  I 
can then set my email client to connect to port 25 on the server 
(10.1.0.1) to send its outgoing mails.


One other thing that I do here that you may want to consider is to then 
have your SMTP server relay the outgoing mails through your ISP's SMTP 
server.  Many mail servers block incoming emails that come from an IP 
address that they know is marked as being within some ISP's dynamic IP 
range.  Relaying the emails through your ISP's server solves that problem.

HTH,

DR