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The Graveyard - Products No Longer Supported => Routers / COVR => DIR-600L => Topic started by: Adeepti on August 03, 2014, 08:35:16 AM

Title: "The DNS server is not responding"
Post by: Adeepti on August 03, 2014, 08:35:16 AM

I'm seeking assistance for a problem I believe lies in my DIR-600 router.

Hardware version: B5
Firmware: 2.17 (updated to the latest)
Region: Germany
Internet: Unitymedia cable modem

Whether surfing on my Android phone, iPad, or Windows 7 laptop, my internet will occasionally stop working. When I run the diagnostic on Windows 7, the response is always "The DNS server is not responding."

The same error always occurs whether the laptop is connected ethernet only (with WIFI disabled) to the router, or WIFI only. Thus I think the problem is not the wireless. The internet cuts out for all devices and not just one, therefore it is not merely one device.

If I run ethernet directly out of the cable modem into the laptop, this problem never occurs. Thus, I believe the problem lies in the router.

Every time, the problem is temporarily solved by resetting the power on the cable modem by cycling the power. Resetting the router never makes a difference. Once the modem is reset, internet access is restored- for a month, a week, an hour. Lately more like an hour. Then it's out again. This has been a problem since I first started using this service with this router two years, ago, but now disconnections are so frequent I must solve the problem, and it's not the ISP.

I've tried changing the primary DNS servers to GoogleDNS or OpenDNS. Same problem occurs. I've tried changing various settings within the DIR-600, and a factory reset. Same problem occurs. While changing some router settings, I succeeded in getting slightly different error messages from the Windows troubleshooter: "Windows can't communicate with the device or resource (primary DNS server.)"

Any help would be much appreciated. Thanks!

Title: Re: "The DNS server is not responding"
Post by: FurryNutz on August 03, 2014, 08:49:26 AM

Link>Welcome! (http://forums.dlink.com/index.php?topic=48135.0)

• Has a Factory Reset (http://blog.dlink.com/what-is-a-reset-button-when-should-i-use-it) been performed?
• Was a Factory Reset performed before and after any firmware updates then set up from scratch?

FW Update Process (http://forums.dlink.com/index.php?topic=42457.0)

• Was the router working before any firmware updates?

Internet Service Provider and Modem Configurations

• What ISP Modem Mfr. and model # do you have?
• Is ISP Modem/Service using Dynamic or Static WAN IP addressing?
• What ISP Modem service link speeds UP and Down do you have?
• Check cable between Modem and Router, swap out to be sure. Link> Cat6 is recommended. (http://en.wikipedia.org/wiki/CAT6)
• Check ISP MTU requirements, Cable is usually 1500, DSL is around 1492 down to 1472. Call the ISP and ask. Link>Checking MTU Values (http://forums.dlink.com/index.php?topic=53008.0)

Router and Wired Configurations
Some things to try: - Log into the routers web page at 192.168.0.1. Use IE, Opera or FF to manage the router. Besure to log into the Admin account on the router.

• Turn off Advanced DNS Services if you have this option under Setup/Internet/Manual or under Setup/PARENTAL CONTROL/Set to>None: Static IP or Obtain Automatically From ISP.
• Enable or Disable Use Unicasting (compatibility for some ISP DHCP Servers) and test under Setup/Internet/Manual. Disable may help with speed performance on higher speed ISP services.
• Turn off DNS Relay (http://forums.dlink.com/index.php?topic=45143.0)  under Setup/Networking. Link>Finding Faster DNS Addresses using Name Bench (http://forums.dlink.com/index.php?topic=53222.0) and input new DNS addresses under Setup/Internet/Manual.
• Setup DHCP (http://forums.dlink.com/index.php?topic=58017.0) reserved IP addresses for all devices ON the router. Setup/Networking. This ensures each devices gets its own IP address when turned on and connected, eliminates IP address conflicts and helps in troubleshooting and maintain consistency for applications that need to connect as well as mapped drives.
• Ensure devices are set to auto obtain an IP address.
• If IPv6 (http://en.wikipedia.org/wiki/Ipv6) is an option on the router, select Local Connection Only under Setup/IPv6.
• Set Firewall settings to Endpoint Independent for TCP and UDP under Advanced/Firewall. Enable or Disable SPI (http://en.wikipedia.org/wiki/SPI) to test.
• Enable uPnP (http://en.wikipedia.org/wiki/Upnp) and Multi-cast Streaming (http://en.wikipedia.org/wiki/Multicast) under Advanced/Networking. Disable uPnP for testing Port Forwarding rules. Enable IPv6 Multi-cast Streaming for routers that have a Media Server option. Disable IPv6 Multi-cast Streaming if IPv6 or Media Server is not being used.
• Turn off WISH (http://forums.dlink.com/index.php?topic=40459.0), and WPS under Advanced.
• WAN Port Speed set to Auto or specific speed? Some newer ISP modems support 1000Mb so manually setting to Gb speeds can be supported by the router. Advanced/Advanced Networking/WAN Port Speed
• Set current Time Zone, Date and Time. Use an NTP Server (http://forums.dlink.com/index.php?topic=48695.0) feature. The DST setting is only needed in the NA region. Tools/Time.

Title: Re: "The DNS server is not responding"
Post by: Adeepti on August 03, 2014, 09:01:48 AM

Yes, a factory reset was performed both before and after the update to firmware version 2.17.

The same problem has persisted from the beginning, though in the past it was less frequent.

Title: Re: "The DNS server is not responding"
Post by: FurryNutz on August 03, 2014, 09:11:32 AM

Please give some feedback to the questions provided so we can get a better idea of your system. Please try some of the suggestions as well.

It could be after trying some of the suggestions that the unit could be faulty.