Internet browsers randomly not loading.

[ScottD536]

Hi,

 

I work in a College in Cambridge and we are having very odd, intermittent issues with Internet pages randomly not loading (e.g. Page not Found or Page cannot be loaded). We are using Windows 10 Enterprise in a domain environment. Students have local user accounts via AD and staff have roaming profiles, but this problem affects staff and student alike. We have checked with our ISP and they cannot see any problems at their end.

 

A quick refresh usually fixes the problem, but it's happening all over the College to all users. It doesn't sound like a massive problem but when you are going through payment sites or any kind of form submission it is a nightmare as you lose everything! We primarily use IE11 for staff and students but we also use Chrome and Firefox, and come across the same issue regardless.

 

Has anyone experienced anything like this, on this kind of scale?

 

thanks in advance!

[Sagima]

The first thing I would do is check your dns server's ettings. Maybe change the external dns lookups to be your ISPs dns servers or google's (whichever they currently aren't)

[kennysarmy]

Hi,

 

I work in a College in Cambridge and we are having very odd, intermittent issues with Internet pages randomly not loading (e.g. Page not Found or Page cannot be loaded). We are using Windows 10 Enterprise in a domain environment. Students have local user accounts via AD and staff have roaming profiles, but this problem affects staff and student alike. We have checked with our ISP and they cannot see any problems at their end.

 

A quick refresh usually fixes the problem, but it's happening all over the College to all users. It doesn't sound like a massive problem but when you are going through payment sites or any kind of form submission it is a nightmare as you lose everything! We primarily use IE11 for staff and students but we also use Chrome and Firefox, and come across the same issue regardless.

 

Has anyone experienced anything like this, on this kind of scale?

 

thanks in advance!

 

Local proxy being overloaded? Running a smoothwall or anything similar on site?

[Michael]

I would say check internal DNS first also.

[ScottD536]

We have tried changing DNS from Google to internal and sadly no change. Not running any proxy or filtering at the minute.

[Michael]

We have tried changing DNS from Google to internal and sadly no change. Not running any proxy or filtering at the minute.

 

Presumably all DNS requests are made internally first (to your on site DNS servers), then to the likes of Google or other? And not directly to Google. That wouldn't make sense in a domain scenario. I would definitely check the health/status of your internal DNS, I can't come to any other conclusion.

[ScottD536]

Yes all requests go to internal DNS servers first, then to ISP'. We did originally use Google at first but changed in order to try and solve this problem, no change unfortunately. As far as we can tell, DNS internally is working as it should be and we have not made any major changes that could have caused this.

[synaesthesia]

A couple of my schools are having similar issues as of yesterday afternoon with nothing obvious showing up internally. Can I ask who your provider is/what your filtering is please? What's your NSlookup like from clients?

[ScottD536]

ISP is Janet, and currently we do not have filtering in place only Cyberoam firewall. NSLookup just shows local DNS server IP address from clients, unless I have misunderstood the question (which is highly possible)!

[Michael]

I guess the other possibility is a switch problem, but doesn't sound like it's isolated to one area!

[ScottD536]

No it seems to happen all over! Will keep digging but so far seems a bit of a mystery..

[ScottD536]

Just to close this thread off, we eventually found out that our Firewall was not strong enough to support the amount of devices that were attempting to access the internet. We have now seriously upgraded the hardware and the problem has subsided! Thanks everyone for the help.