blocked 443 port

[Bob Proulx]

Phil Marsh wrote:
> Strangely enough, I never had a problem reaching my server via its IP name,
> except when I tried to reach port 443. Now it seems to work?

Of course as I am sure you know the port is completely independent of
the domain name.  Those are two separate things.  If you are
connecting to something then for the most part the flow goes like
this.

* Step 1: Resolve the name to an IP address.

* Step 2: Open a TCP connection to that address on the specified
  port.

The port used is part of the TCP connection.  But the TCP connection
uses an IP address which was resolved in the previous step.

Most likely is that a firewall is blocking connections based upon
port.  Or also possible is that a temporary glitch across the global
Internet WAN has a temporary failure which goes away after a moment.
For our home built stuff sometimes routes that we don't test have bit
rot and get broken but we don't notice until we go to use them.

But if it started working again after a short time I would guess it
would be a temporary glitch in the global Internet WAN routers.  Which
I see every so often from cron scripts and stuch.

Bob