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Upon returning from a trip during which I was able to access my server (https/ssh) only hours before, I discovered that all attempts to connect to the server internally are timing out. I have tried from Mac OS X, Windows 10, and Android 7.1 devices.
I have tried rebooting each device in question, as well as power cycling the router and even doing a factory reset on the modem/router in question (a NetGear AC1900/C6300BD). I have also looked through all the configuration screens and cannot find anything regarding "NAT loopback" or anything like that. It was working before I left, and had been working fine for months. I have set up port forwarding and it works fine if I am coming in from outside the network, but inside it just won't connect - it times out.
I have tried various things to get the host name to resolve to an internal device, as this would probably be the ideal solution, but have not been entirely successful.
Update: After pursing getting internal DNS to resolve the server's host name to an internal IP address I am starting to think that approach isn't viable. Specifically, devices that were working (e.g. Windows 10) have inexplicably stopped working. After rebooting the Windows 10 device I was again able to access the server until it came out of sleep, at which time it started timing out trying to connect. Inspecting the web page indicated that pages that were working were being loaded out of cache from the external address, despite the fact that networking properties show the proper DNS servers, and commands such as ping see the correct internal IP address.
Michael
Posted 2016-12-26T10:01:12.100
Reputation: 2 242
Are you accessing the server via IP address of domain name? – xR34P3Rx – 2016-12-26T10:47:48.443
Assuming the devices are still able to access the internet in other ways, I think your ISP have (intentionally or otherwise) made a change that's caused (permanently or otherwise) the effect you describe – Reg Edit – 2016-12-26T11:06:37.183
@xR34P3Rx Yes, although it's a 2nd level domain. – Michael – 2016-12-26T17:52:26.517
@RegEdit I had that thought, although I'm having trouble coming up with how they could have done that since packets shouldn't actually be going past the router. I did contact them to ask them if anything had changed on their end but the response was... inconclusive. – Michael – 2016-12-26T17:53:12.100
Have you checked if your IP has changed? or do you have a static IP? – xR34P3Rx – 2016-12-26T17:54:14.437
@xR34P3Rx The IP address did change in the process of resetting the router, but DNS is dynamic and started reporting the new IP address immediately. – Michael – 2016-12-26T18:17:44.977
what do you get when you run
nslookupon the domain andping [domain-name]? i would also run atracerton your public IP and see where its going. – xR34P3Rx – 2016-12-26T18:21:14.053@xR34P3Rx
pingtimes out.nslookupreturns the world visible address of the server.traceroutenever returns any hosts, e.g.1 * * *– Michael – 2016-12-26T18:36:52.933i have a similar "issue" at home with my domain. If i configure my outside access as
www.test.comthen it works but if i use the top level domain, it doesnt and thats from outside. Inside i cant connect at all and i read a while back that it seems like the router is the one blocking that. Not sure if the same applies to you. But why do you want to access your server from the inside with your external address? why not use internal? – xR34P3Rx – 2016-12-26T18:49:37.440@xR34P3Rx I would love to have the server accessed using only the internal address, but there are numerous issues trying to get a solution working where every device gets the proper internal address for the host name. – Michael – 2016-12-26T19:08:17.037
what i do at home is i have my own DNS server and i assign individual devices a DNS Host name. My raspberry pi for example is music.xx.co, my NAS is nas.xx.co and so on. As for outside access. for some reason i cant connect using xx.co but i can with www.xx.co as a subdomain. and im ok with that now. – xR34P3Rx – 2016-12-26T20:25:46.333