I'm running into a really bizarre issue that has me banging my head against the wall. Hoping someone here can point me in a direction I haven't explored yet.
I do IT work for a small insurance company. They informed me that two days ago, one of the websites they frequent was no longer loading. The website in question is for the Massachusetts RMV (https://atlas-myrmv.massdot.state.ma.us). When I took a look at the error, it was a DNS error saying the address couldn't be resolved. This error was happening on all the computers on the local network, with multiple browsers, incognito and not. Trying to ping the site also fails without resolving to an IP.
The website in question resolves on all other systems I've tested outside the local network. It even works on one of the business workstations (a laptop) when you connect it outside the network.
I've tried disabling AV and firewall with no effect.
Restarted the network firewall and even disabled it just in case it was blocking something. Wouldn't make sense if it was blocking DNS lookups for one website, but figured it was worth trying.
They are running on a local domain and their DNS server was set as the local Windows server. So I tried manually setting the DNS on one of the systems to OpenDNS servers (and ran /flushdns and restarted). No change. Note that the OpenDNS servers are the same servers I use on my own computer that the website loads without issue on.
I've checked the hosts file to make sure there was nothing in there -- there wasn't. Though that wouldn't explain why the business workstation works outside the network, figured it was worth checking.
I'm really at a loss here. DNS lookups are clearly working because all other sites load. If something was blocking DNS lookups, it wouldn't only impact ONE site. Plus I've ruled out any of the items that could potentially be blocking it (unless I'm missing something).
Any thoughts as to what this could be?
UPDATE: The issue has seemingly resolved itself. If the issue returns I'll make sure to post results from nslookup
UPDATE2: The issue appears to have returned inexplicably. I've run nslookup using a number of different DNS servers and the result is the same for each one.
PS C:\Windows\system32> nslookup atlas-myrmv.massdot.state.ma.us 208.67.220.220
Server: dns.opendns.com
Address: 208.67.220.220
DNS request timed out.
timeout was 2 seconds.
*** dns.opendns.com can't find atlas-myrmv.massdot.state.ma.us: Server failed
PS C:\Windows\system32> nslookup atlas-myrmv.massdot.state.ma.us 8.8.8.8
Server: dns.google
Address: 8.8.8.8
*** dns.google can't find atlas-myrmv.massdot.state.ma.us: Server failed
PS C:\Windows\system32> nslookup atlas-myrmv.massdot.state.ma.us 1.1.1.1
Server: one.one.one.one
Address: 1.1.1.1
*** one.one.one.one can't find atlas-myrmv.massdot.state.ma.us: Server failed
Running nslookup on other domains works fine and returns IPs (google.com, microsoft.com). Also, when I run nslookup on my machine for the problem domain with the same nameservers as above, I get a response. What would cause a DNS request to fail for one specific domain only from a particular LAN? I'm stumped.
