Odd Connection Occurence

I'm not really sure how to describe this, but I found it really weird.

Recently, I've noticed that the internet connection here at home gets rather inconsistent at times. Connection to most websites seems to be unavailable. For some weird reason though, I am still connected to Yahoo messenger. When I troubleshoot it, it says "DNS server is not responding".

Now to add to the weirdness, almost all the computers at home are affected by this, except my M18x. I still have full access to the internet with it even if the other computers don't.

I just find this really unbelievable and I can't seem to find a good explanation for this. I really hope someone could enlighten me on this.

 

Depending on the router and how it is configured, if the primary and secondary DNS info is incorrect or for some reason has changed that can be the reason. Can you access your router config? Is this a model straight from the ISP or do you have a firewall/router deployed that you set up. The m18x can be working possibly because there are fixed IP information including subnet, gateway, and dns statically? If you can manage the router and there is static IP info, you might want to add 8.8.8.8 for your secondary dns (this is google's which never changes). From the affected computers try this
1- click on windows start button
2- in the search line type in cmd (command prompt)
3- when the dos window box appears type in ipconfig /flushdns, then ipconfig /release, then ipconfig /renew
4- after that is all done, open your browser and see if all websites finally show up when you surf, if not, then it can be that the computers have static IP info that is manually inputted and incorrect or the router has a problem

This is under the assumption that the computers are getting IP information by DHCP. Another reason is that those affected computers may have a proxy setting in the internet connection settings (sometimes caused by a virus) which forces all traffic to a specifc address, or the host table file redirecting all queries. With networking there are many areas that can cause such name resolving matters.

Forgot to add, hit enter after every "ipconfig /..." entry to run the command, then do it for the next 2 I wrote in step 3. Also wanted to ask, are you having this issue with wifi, wired, or both?

to see what and where you are getting the IP infomation, using the same cmd command prompt window, type in ipconfig /all, hit enter and the network adapter that you are using to connect will have info on the IP address assigned to the pc, subnet, gateway, and dns info on it that should tell you where that computer is picking up the info (usually the gateway ip is also the dns and dhcp servers), you may have to scroll up that box to see it all. There are other commands that can help resolve issues with dns and ip related such as nslookup, ping, and tracert. All effective tools for IT supporting.

 

Simple answer. And one of the first things to check.

Check the DNS IP Addresses on the Router and Computers.

You could try changing them to Public DNS IP's such as opendns = 208.67.222.222 and/or google dns = 8.8.8.8 and see if that helps.

After you make the change on the computers you may want to run the command prompt in admin mode with these commands. ipconfig /flushdns and then hit the enter key; then ipconfig /registerdns hit enter key

 

Thanks for the info. I'll try it in case it happens again.

Forgot to add that I use wifi connection. The modem from the ISP is hooked up to our wifi router and I never really have tried using a direct connection with a LAN cable.

Another odd thing I noticed is that there still appears to be a connection since I can still chat with some of my buddies online. I just can't access majority of the sites. There are times that I can still access NBR though.

 

This is because programs like skype, messenger etc. does not use DNS. DNS is used to load/fetch/lookup web sites.