[squid-users] Strange problem with 503 errors.

My college recently switched from ISP provided IPs to its own.
202.128.71.x, 202.128.72.x, 202.128.73.x and 202.128.79.x from
ISP to there own 203.215.52.0/22.

The switch seemed to go fine, but have found a few sites that are
giving us 503 errors.

I have gotten around the problem by using rinetd to redirect a port
to the squid server on my home machine for these sites, and one
of our ISPs has given access to there proxy server so now using
that, but ideally would like to come up with what is causing the
problem.

I have squid servers on campus, and was wondering if there was
a way to have them in the event of not being able to connect to a
site, it they could automatically try going thru the ISPs proxy?

The traceroutes to the sites that don't work get to the point right
before they should, 1 hop less. The latest problem site is strange.

Going to tinyurl.com sometimes gives the IP address
64.62.243.89, which works fine. But other times it gives
64.62.243.91, which doesn't from the college. Both work fine from
home. In running wireshark, the 89 address will send and receive
pings and responses, but the 91 only shows the sends with no
receive responses.

nmap shows no open ports on the 91 from college, but from home
it does? Perhaps someone might have a way of figuring out what
the issue is. Our IT guys say they are not blocking these IPs, and
even they have found sites that don't work for them.

Thanks.

+----------------------------------------------------------+
  Michael D. Setzer II - Computer Science Instructor
  Guam Community College Computer Center
  mailto:mikes_at_kuentos.guam.net
  mailto:msetzerii_at_gmail.com
  http://www.guam.net/home/mikes
  Guam - Where America's Day Begins
  G4L Disk Imaging Project maintainer
  http://sourceforge.net/projects/g4l/
+----------------------------------------------------------+

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Received on Fri Apr 06 2012 - 04:55:49 MDT