[RndTbl] Shaw now blocking SMTP port 25

Sean Cody sean at tinfoilhat.ca
Fri May 25 10:24:18 CDT 2007

On 23-May-07, at 6:09 PM, John Lange wrote:

> On Wed, 2007-05-23 at 10:33 -0500, Sean Cody wrote:
>> The general rule of thumb is to always use the DNS and SMTP relay of
>> your immediate upstream provider anyways.
> Yup but this is a serious pain in the *ss if you work constantly  
> from a
> laptop like I do. You'd have to change the settings every time you  
> move.

One thing I've done for a few $large_crown_corp people was run the  
services being blocked on high ports (ie. 25 -> 2525, 22 -> 2222).
One amusing thing I've found is many $large_companies will block SSH  
but allow telnet so a nice solution is to listen sshd on both (or a  
simple redirect).
There hasn't been a firewall yet that I could not break out from.  :P

I was also reading an article a long while ago that suggested the  
possibility of distributing upstream service information via DHCP  
which I found interesting.
Of course the dhcp client has to support it but that would make  
things VERY easy.

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