Can't access uni website from our home network

Hi,

We've had this problem intermittently for a few months now. We thought it was the uni having problems, since we aren't having problems with other sites and every computer and browser on our network that we tried couldn't get to the site, but now we're pretty sure that we're the ones with the problem. We've had friends check if they can get to the uni site and they have been able to at times when we can't. Sometimes we can get there, sometimes we can't. But friends CAN get there when we can't.

Some notes before we go on:
Our uni site is http://www.utas.edu.au - it's necessary to use the www.
The uni IP address is 131.217.10.29
Three other domain names are hosted on 131.217.10.29, which have uni involvement:
www.tpac.org.au
www.landscapelogic.org.au
www.bluenet.org.au

I've tried various things tonight:

• I can access the uni home page by typing the IP address into my browser.
• I can't get anywhere from the home page using the links after typing in the IP address.
• I can ping the uni by IP address.
• I can't ping the uni by name.
• Pinging utas.edu.au using the -a option didn't give me back a name.
• I can't reach tpac.org.au in my browser.
• I can't ping tpac by name.
• I can reach the other two sites with my browser.
• I can ping by name the other two sites.
• After pinging landscape and then bluenet by name, using the command "ping -a 131.217.10.29" gave back the info that this IP address belongs to the landscape address.

The only security software on our computers that would be common is Spybot; it's not to do with the host file because this computer doesn't have any entries in the host file. (My memory is that it used to so maybe someone that stayed here and proved untrustworthy replaced it. However, that only serves to suggest it's not Spybot unless there is something else about it that I don't know.)

So that's leaving us wondering if the problem is in our modem/router. I've poked around and can't see anything. Anyone know if there's some sort of DNS cache that can be flushed? It's a Netcomm NB5Plus4. Here's a link to the page about it with links to manuals:
http://www.netcomm.com.au/netcomm-products/adsl-broadband/nb5plus4

Any other suggestions? Oh, and we don't think it's the ISP because friends have just signed up with the same ISP as us and they can get to Utas.

Can someone try pinging utas.edu.au and see if you can?

I've attached the results of my cmd tests.

Any help very welcome - my son can't reach his emails, course notes, timetable changes, etc., pretty much ANYTHING uni related.

 

Anytime you can not resolve domain names to IP addresses you most likely have a DNS (Domain Name Server) issue.

From command prompt execute a IPCONFIG /ALL command and post the response. We are specifically looking for the DNS entries in the response.

Oh, do this from the machine that is having the problem.

 

Perhaps I didn't make it clear enough - NO browser on ANY computer here in our home network can reach the uni website. The machine that is having the problem is all of them. However, here is an ipconfig/all which correctly shows the modem being our DNS:

 

OK.

Lets try an experiment. Change the DNS entry manually to 208.67.222.222 and 208.67.220.220. Then give it a go and let me know what happens.

 

OpenDNS I notice.

Not being entirely sure what you meant by "manually" I opened up my modem and tried to change it in there. No dice. Maybe I'm doing it incorrectly. So I opened up My Network and changed the DNS servers for this computer's LAN connection. Bingo! I'm getting there and pinging successfully. So what does this tell us?

But having got this far will make things a lot easier for my son so thank you for where we've got to so far!

 

This is exactly where I wanted you to change it.

OK....one more little test. Jot down the DNS settings in your router and plug those into your MY NETWORK and see if it works OK or begins to fail.

 

If I'm not mistaken, there are no DNS settings in my modem - they are automatically assigned from the ISP. However, I can probably figure out what they are and plug them in manually and see what happens. Does that help?

I've been poking around my modem and haven't noticed any DNS settings anywhere, only something about them being automatically assigned. Again, if it helps any, the manual for my modem can be found at the above link. I'm poking through the manual and wandering around the modem but some of it only half makes sense to me still. And some not even that much! :-D

 

No sorry....you have perhaps misunderstood. There should be a status or something when you are logged into the modem that will show you what DNS addresses the modem is using...not that you should change them. Jot those addresses down and apply them to your MY NETWORK where you put the opendns settings.

 

What link?