unable to reach specific web site

[dphantom]

There is a web site we are unable to reach from some PCs and servers, but not others. All other web sites are reachable.

We have a ISA 2000 server providing proxy caching. I have removed the proxy from our browser settings, cleared cache, cookies, temp files and still cannot get to this one site.

Pix firewall is wide open outgoing, restricted to usual SMTP, HTTP traffic inbound.

Our internal DNS seems fine, no other netowrk issues.

We are using IE6 and either Windows 2000 or XP SP2.

Any ideas??

 

[drinkmorejava]

you sure you do have any routers or managed switches/hubs stuck away somewhere with site blocking. It doesn't neccesarily have to a main server messing it up.

 

[dphantom]

Absolutely positive.

I did some googling and found a couple posts but nothing that helped.

 

[Rapidskies]

Have you tried going to the website via IP address yet? That would tell you if its a DNS issue or not.

 

[casper114]

Have you tried more then one type of web browser to access the site? Sometimes sites are made for a specific web browser.

 

[dphantom]

Have tried by its IP address and no luck. Can do a trace route. Can ping the external web site. Can use IE, Firefox, etc to reach site from outside the netowrk, but inside our network regardless of browser we cannot reach the site.

I'm thinking it is DNS related too, so am working with our ISP. We took the Proxy out of the picture to remove one variable, still no luck.

 

[Rapidskies]

Well if getting to it via IP does not work then it is not a DNS issue. What about MTU packet size on your firewall/router try setting it to 1400 and then see if you can get to it.

 

[tbrooks40]

look in internet options and make sure its not listed under your list of restricted websites...

start / cntrl pnl / int options / security tab / sites

some adware programs will restrict certain sites known for aggressive spy/pest/adware tactics.

i know spybot does it if you have real time security enabled.

good luck

rtb

 

[tbrooks40]

oh yeah, there may be a limit on the number of connections allowed for the site you are visiting. i read this recently somewhere... i'll try to find the article... until then...

edit to add... if the above is the case then check the website again after a 10 or 20 minutes giving some of the current sessions time to expire.

still looking for that article... thought it was on SearchWinSystems.com but i'm not certain :disgust:

 

[dphantom]

Thanks, tbrook, but already tried all that too. No restrictions in Internet Explorer anywhere. We don't use Spybot, our staff don't like it - interferes with their job. :thumbsdown:

I've talked to the network guys at the site in question. They say they have no limits on concurrent connections, I tend to believe them as it is a public university site.

I have found one, just one, PC on our internal network that can get to the site in question. Yet, as far as we can see, it is an identical replica to over 100 other ones. We are going over it with a fine comb to see if there is a difference somewhere in configuration, whether it be in scripting, DNS, Proxy, whatever.