[wellylug] re:Website not visible

[Cliff Pratt]

John Durham wrote:
> I just searched for logs (thanks Andre) and found two:
> /var/log/apache2/access.log.1
> The last 2 entries here were:
> 65.55.208.140 - - [15/Jan/2007:18:45:48 +1300] "GET /indexaccounts.html
> HTTP/1.0" 200 31036 "-" "msnbot/1.0 (+http://search.msn.com/msnbot.htm)"
> 70.190.160.21 - - [15/Jan/2007:18:46:03 +1300] "POST /cgi-bin/links2.cgi
> HTTP/1.0" 500 16184 "http://modecideas.com/links2.html" "Mozilla/3.0
> (compatible)"
> 
> /var/log/apache2/errorlog.1
> The last 2 entries in this one were:
> [Mon Jan 15 18:46:03 2007] [error] [client 70.190.160.21] (2)No such
> file or directory: exec of '/var/www/modecideas.com/cgi-bin/links2.cgi'
> failed, referer: http://modecideas.com/links2.html
> [Mon Jan 15 18:46:03 2007] [error] [client 70.190.160.21] Premature end
> of script headers: links2.cgi, referer:
> http://modecideas.com/links2.html
> 
> The error is probably a simple script header problem easily fixed. The
> script is a dummy place holder of little importance.
> 
> After this both logs just stop. The server has been re-started without
> result. Port 80 does not show up in netstat any more.
> 
> I'm very puzzled.
 >
Here's why port 80 is important.

http://www.networksorcery.com/enp/protocol/ip/ports00000.htm

Each port relates to a service, and in particular port 80 relates to the 
'http' service (which represents a web site). A client sends a request 
to port 80 on your machine from a 'high order port'. The request is a 
request for a page. Your machine responds with a page to the client on 
the 'high order port' from port 80 and the client's browser interprets 
the page. A 'high order port' is just a high number port.

All communications between your web server and the client's browser are 
pages, even when scripts on the server are involved. Scripts merely 
generate a page.

You said in a different post:
"TCP ports it is listening on include 139, 878, 111, 22, 631, 5432, 25
UDP ports are 137, 138, 111"

For example port 22 is ssh. You can connect to the server on port 22, 
5432 is PostgreSQL, etc. Those have nothing to do with your web service 
as such.

(But you probably knew most of that)

Cheers,

Cliff