Airport Extreme Suddenly Not Working (Sort of)

Thanks.. the screenshots makes it easy..

Once you finish I would definitely just turn off the ATT modem and the AE .. wait about 20min and you should power on the modem again followed by the AE and public IP will change.. and you will be fine.

The DNS is wrong.

Unless you are fiddling it should definitely not be 172.16.0.1

I am not sure how things worked before you went away.. but you have set the AE to 192.168.x.x IP range.

However in the ATT router you selected 172.16.0.x

That is why the DNS is wrong.. But I am not sure you should set to the 192.168.1.0 as that is used by the AE now. This is how DMZ setups get messed up.

So first thing I would do is set DNS directly in the AE to 8.8.8.8

And for second DNS I would probably use the ATT DNS .. (that is the public one assigned to your ATT router more than likely).

AT&T DNS Servers

Primary DNS: 68.94.156.1

Secondary DNS: 68.94.157.1

There is another issue with Domain..

Your AE picked up attlocal.net from the main router.. this is messy.. and Apple routers don't like being assigned domains.. check what your computer is getting.

I have it set to local .. the best value for you with DMZ is probably blank for the search domain.

You can use the -ve button on the bottom to remove that domain.

Your main DNS server is likely to be 192.168.1.1 but secondary is 8.8.8.8 or the ATT DNS.

The DNS is the main cause of websites not working.

Exactly which version of the Extreme? If tower just say tower.. but if one of the earlier models look on the base and tell us the model on paper label or moulded into the rubber. eg A1408 is Gen5.

About how old if you can remember.

Is the ATT router passing the public IP to the Extreme? Or full DMZ mode it should be ok.. but I would assume something has happened and the ATT router is not actually giving it full DMZ.. hence why some sites are working and some not.

I would go back to a more standard arrangement. So forget about the DMZ..

Put the AE back into bridge mode.. and see if it then works ok.

If so you can do a neat setup to have AE take over much of the role of router without causing issues..

but I'd rather just keep my setup since I have no clue what's going on.

If you really want to pursue this.. we need a full set of screenshots from your AE to see what is happening.

I particularly want to see on the computer what DNS and search domain you are picking up.

• Set my first DNS on the AE to 8.8.8.8, and the second to 68.94.156.1

Yes..

• As of right now I don't have the attlocal.net wrote in to the line. If I delete it, it just comes back on it's own. What should I do there?

There is probably not much you can do about the domain on the AE.. which as you say is set automatically.. unless you fix it on the ATT router.. in which case I would change it to local which is what Apple is set to by default.

Just make sure it is removed on the clients.. if they are setting attlocal.net as search domain that is a problem.

Don't worry about the reset.. today or tomorrow.. do your actual network setup and get everything straight.. posting the details when they change perhaps every 24 hours anyway is no big deal.

And I would still go back to using the AE in bridge.. turn off the DMZ.. I think you are making life so much more complicated..

If you particularly want the AE controlling things then you can use DHCP only.

But it is tricky to setup..

You must reboot the computer as well.. to clear the DNS..

And it could all start working nicely tomorrow.

I would try pinging the websites that are not responding in terminal.. just open terminal and type

ping abc.com and see if it responds. A dns error should show as the computer cannot resolve the address.

Also IPv6 can get really messy.. I would turn off IPv6 in the AE and see if that fixes things.

But in the end this is a poor setup. Why it should fail while you were away is something I am unsure of.. but the seeds of its own destruction are built into the configuration.