D-Link Forums

The Graveyard - Products No Longer Supported => Routers => DIR-880L => Topic started by: tgfrules on October 18, 2014, 01:08:12 AM

Title: DNS issue with Internal DNS server
Post by: tgfrules on October 18, 2014, 01:08:12 AM
My setup is like the following.
I use the D-link 880L router with 5-10 client devices.
One of these devices is a Windows Server 2012 which I have set up as a DNS server.
What I did on my old D-link DIR-655 router (and was working just fine for many years) was the following
Router IP: 192.168.5.1
DHCP scope: 192.168.5.50 to 192.168.5.200
Primary DNS server: 192.168.5.10 (the IP of my internal DNS server)
Secondary DNS server: 8.8.8.8 (thats the google DNS for backup in case my internal DNS is down)
DNS relay: False

This resulted in the router would broadcast the two DNS servers to all my client thus making my clients use my internal DNS server. Everything was working just fine.

Now I have setup the same settings on the 880L (well the 880L interface is very different from the DIR-655).
The clients are now getting the two DNS servers just fine (and two extra DNS server which I do not know why - anyways that is not the problem).
The problem is when I set the my internal DNS server to a static IP (the 192.168.5.10) the network traffic is "blocked". I can't even ping the router directly (192.168.5.1) let alone anything else.
If set the DNS server to get an IP automatically (enabling DHCP) it works just fine. But I can't really use that since the IP would be wrong and all my other clients can't get hold of it (when they need for internal DNS lookups)

It seems to me that in the 880L there is a bug when you set a IP of device to the same as the specified DNS server. I hope I have stated my problem clearly and looking forward to any feedback.

Thanks!
Title: Re: DNS issue with Internal DNS server
Post by: PacketTracer on October 18, 2014, 05:55:36 AM
Hi,

Quote
The problem is when I set the my internal DNS server to a static IP (the 192.168.5.10) the network traffic is "blocked". I can't even ping the router directly (192.168.5.1) let alone anything else.

What kind of network traffic is exactly blocked? Any traffic originating from any LAN PC to the router address (.1) or the Internet? Or just the traffic originating from your internal DNS server (.10)?

If only the second case is true, another theory could be that the DIR-880L has an implicit filter allowing only outgoing traffic originating from the "DHCP scope" (.50 - .200). Hence give it a try and extend this range to .10 - .200 this way including your (still statically configured) internal DNS server. DHCP server (and DHCP client) mechanisms still assure that .10 is not deployed a second time when it is already in use (by your internal DNS server).

PT
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on October 18, 2014, 07:17:40 AM
From the 192.168.5.10 server I can't ping the router (192.168.5.1) or stuff like 8.8.8.8. But I can ping other local machines on the network like 192.168.5.11. From the 192.168.5.11 server I can ping the router (192.168.5.1) and 8.8.8.8 just fine.

I did try to extend the DHCP range to include .10. I restarted 192.168.5.10 and no change. Also 192.168.5.11 still works after the extentions.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on October 18, 2014, 07:47:23 AM
Link>Welcome! (http://forums.dlink.com/index.php?topic=48135.0)


If you set back to default settings with 192.168.0.1 on the 880L router, default DHCP pool address of .100 to .200, set a static IP address on this other DHCP server with DNS support to 192.168.0.10, and all other client devices to Dynamic IP addresses, can you ping and connect from this DNS server PC to the router?

Is the DHCP server portion of this PC enabled or disabled? Having 2 DHCP servers on the same network can be problematic, even though this worked on the prior router model. There maybe some differences on newer generation models.

Is this model router being used in a home or business environment?
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on October 18, 2014, 08:37:35 AM
It's the 880L HW version A1, Firmware 1.01, region EU.
There is no ekstra running DHCP server in the network.
The router is being used in a home environment - even though I don't understand what that could influence :)

I did what you proposed and reverted to the 192.168.0.X range and only had the DNS server on fixed 192.168.0.10 IP. The internet came back and everything seemed fine. Then I changed the Primary DNS setting on the router to 192.168.0.10 and then problem came back. To me this problem is directly related to the Primary DNS setting on the router which seems cannot be the same as an already used IP in the network.
Title: Re: DNS issue with Internal DNS server
Post by: PacketTracer on October 19, 2014, 02:27:03 AM
Looks like you really found a bug in the model's present firmware.

Maybe the following is a workaround that meets your demands:

PT
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on October 20, 2014, 11:54:00 AM
Some info I was given, D-Links newer generation routers don't support loopback for security reasons. Older routers did like the DIR-655. I guess having a lookback presented security issues that D-Link had to close thus no longer supporting lookback. It was mentioned that maybe setting up a Virtual Server rule may allow this kind of configuration. My contact will check on this with his DNS server at home tonight and let me know tomorrow.
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on October 27, 2014, 12:50:28 AM
Thanks PacketTracer for your post - It was a good idea.
Add a LAN host route for this address to your DIR-880L: 192.168.51.10/255.255.255.255 next hop: 192.168.50.10 (unfortunately not all D-Link routers allow to configure LAN routes, but only WAN routes. Hope this is not the case with DIR-880L)
It seems that cannot be setup on the 880L :(

FurryNutz - I can't really accept that this is a "security feature". Surely there must be a way to setup an internal DNS using the router.
Title: Re: DNS issue with Internal DNS server
Post by: PacketTracer on October 27, 2014, 07:03:11 AM
Hi,

if you can't configure the LAN route "192.168.51.10/255.255.255.255 next hop: 192.168.50.10" in your DIR-880L, you can configure it on any client of your LAN instead, e.g. with Windows using "route -p add ..." command.

PT
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on October 27, 2014, 11:43:16 AM
if you can't configure the LAN route "192.168.51.10/255.255.255.255 next hop: 192.168.50.10" in your DIR-880L, you can configure it on any client of your LAN instead, e.g. with Windows using "route -p add ..." command.

A good idea that I might need to fall back to. At least something I need to try.
But it will not work on devices such as my iPhone, Sonos and so on.
Title: Re: DNS issue with Internal DNS server
Post by: PacketTracer on October 27, 2014, 03:08:47 PM
Perhaps another idea:

In your DIR-880L leave DNS server configuratuon as is: Primary DNS server: 192.168.5.10 and Secondary DNS server: 8.8.8.8. In addition according to page 97 of the manual (ftp://ftp.dlink.de/dir/dir-880l/documentation/DIR-880L_man_reva_Manual.pdf) enable DNS relay function.

As a consequence your LAN clients get your router's IP address 192.168.5.1 for use as their single DNS server, where the router will relay (at least in theory) clients' DNS requests to your internal DNS server and as a second choice to Google's DNS server if your internal DNS server is down. Maybe in DNS relay mode the DIR-880L does not block your internal DNS server.

PT
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on October 28, 2014, 03:45:56 AM
Didn't work either.

We are running out of options here :(
If this could just be taken as a bug, so I can get a change in the firmware.

It simple does not make any sense that D-Link does not support internal DNS servers.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on November 05, 2014, 03:46:15 PM
FYI, D-Link has this under review to see if this is a supported feature or design or not. My contact could not set up a similar DNS external server and make it work so he's forwarded it on to the lab for analysis.

Please be patient.
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on November 05, 2014, 10:17:24 PM
Thank you - looking forward to a solution :)
Title: Re: DNS issue with Internal DNS server
Post by: slhmtb on November 10, 2014, 04:02:53 PM
I have this same issue. Worked fine on the DIR-655. Spent several hours on the phone with Dlink support trying to resolve it. I hope the new firmware has the fix.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on November 10, 2014, 04:10:47 PM
Link>Welcome! (http://forums.dlink.com/index.php?topic=48135.0)


Internet Service Provider and Modem Configurations

I have this same issue. Worked fine on the DIR-655. Spent several hours on the phone with Dlink support trying to resolve it. I hope the new firmware has the fix.
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on December 04, 2014, 10:09:26 PM
Any update on this issue ?
Title: Re: DNS issue with Internal DNS server
Post by: rojosonic on December 05, 2014, 10:59:04 AM
Same problem here, DIR-868L, HW:A1, FW: 1.09, when i put my local DNS server as primary DNS, i lost access to the internet.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on December 05, 2014, 11:09:16 AM
Link>Welcome! (http://forums.dlink.com/index.php?topic=48135.0)

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

Internet Service Provider and Modem Configurations

Is DNS relay enabled or disabled when you input custom DNS?

Same problem here, DIR-868L, HW:A1, FW: 1.09, when i put my local DNS server as primary DNS, i lost access to the internet.
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on December 14, 2014, 12:35:15 PM
So I revisited the problem and for some reason I found a workaround.

I setup my DC to have a fixed IP (not the DNS server IP) and internet works fine as expected.
Then I added a second IP, this time the DNS server IP (192.168.5.10). Now it seems that the DC is connectable to internet and the clients can find it.
I am not sure why this works now because I am pretty sure I tried something like this before.
Title: Re: DNS issue with Internal DNS server (WORK AROUND)
Post by: FurryNutz on December 14, 2014, 12:49:24 PM
It was mentioned to set a static IP address in earlier posts. Possible a configuration was missed before.

Sound like you have verified a work around.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on January 06, 2015, 02:25:02 PM
Maybe you can detail a step by step instruction for future users if this seems to be working for you well. Would be nice to have some instruction on this for users to look at.   ::)
Title: Re: DNS issue with Internal DNS server
Post by: GewGaw on January 16, 2015, 05:36:04 PM
I would love this to be corrected. As soon as I enter an internal DNS server none of the clients receive DHCP IPs and DNS resolution is  pooched.

Anyone have gotten word if this is being addressed?
Title: Re: DNS issue with Internal DNS server
Post by: tgfrules on January 17, 2015, 01:54:57 AM
As requested here is the workaround for the D-LINK DIR-880L Internal DNS bug.
The bug is when you set the Primary DNS to an internal server the network connection on that server stops.

In order to fix this you setup 2 IP adresses on your internal DNS server like this.
Note that I use the range 192.168.5.XXX which is not default. I see no reason why it should not work with the default range.

First log into your routers web interface. Go to Settings > Internet > Advanced Settings
(http://snag.gy/pNsNV.jpg)
The Primary DNS server IP should be the IP of your internal DNS Server
The Secondary is Googles DNS which secures a fallback DNS if your internal DNS should fail

On the DNS Server the IP settings should be the following
(http://snag.gy/FEy2Y.jpg)
Make sure that the IP address is within the allowed DHCP range
Default gateway is the IP of the D-Link Router

Then click Advanced and add another IP
(http://snag.gy/1f8di.jpg)
The added IP MUST be the IP that you chose earlier as primary DNS server on the router

There you go, a workaround for the 880L DNS bug
Title: Re: DNS issue with Internal DNS server
Post by: PacketTracer on January 17, 2015, 04:03:41 AM
Hi,

this workaround obviously only works, if your DNS server uses 192.168.5.7 when talking to the Internet. Don't know how Windows selects the IP source address if there are more than one configured for the same interface. Maybe the order addresses are shown in your last sceenshot is crucial - where Windows always selects the address shown in the first place when it initiates a connection. If so, it should be emphasized as a general rule that the address configured as "Primary DNS Server" inside the router configuration has to be in the second place inside the Windows IP configuration shown in your last screenshot.

PT
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on January 18, 2015, 10:15:15 AM
And how about some set up information for a interna DNS server? I see some people use Raspberry Pi as a DNS solution. What could users use? Any details on how to set up a DNS server what works in conjunction with a D=Link router would be helpful too.

Thank you for this information. Will copy this to a FAQ sticky for users to use in the FAQ section.  ;)
Title: Re: DNS issue with Internal DNS server
Post by: GewGaw on January 18, 2015, 10:24:13 AM
This workaround isn't possible with some appliance based devices such as Synology or QNAP NAS's. Can we issue a request for bug fix or feature update for the firmware.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on January 18, 2015, 10:27:04 AM
How so?
Please give some details on how its not working for you?

This workaround isn't possible with some appliance based devices such as Synology or QNAP NAS's. Can we issue a request for bug fix or feature update for the firmware.
Title: Re: DNS issue with Internal DNS server
Post by: GewGaw on January 18, 2015, 10:30:04 AM
You are unable to assign a second IP to the same interface. This would mean you need to break a bonded interface (if you are lucky enough to have two or more phyiscal ports on the units) to assign individual IPS to each physical port. I did some some hacks to drop the the Linux shell and add an IP but not exactly a doable work around for most.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on January 20, 2015, 07:09:28 AM
Possibly that this issue and the design isn't meant for more than one physical port for these model routers, again, these are home class routers with the average home user in mind. Generally most home users have no need for any additional ports, servers or internal DNS servers. Home users just want things to work with little hassle and little configuration. This issue may not be addressed by D-Link and is saved for business class routers.  :-\

You are unable to assign a second IP to the same interface. This would mean you need to break a bonded interface (if you are lucky enough to have two or more phyiscal ports on the units) to assign individual IPS to each physical port. I did some some hacks to drop the the Linux shell and add an IP but not exactly a doable work around for most.
Title: Re: DNS issue with Internal DNS server
Post by: Sireone on March 20, 2015, 04:21:29 PM
Same issue here with my DIR-850L.  The workaround I have is to use the DHCP service on my Windows 2008 server and disable it all together on the 850L.  This bug should definitely be looked into.
Title: Re: DNS issue with Internal DNS server
Post by: FurryNutz on March 23, 2015, 06:55:24 AM
Loopback maybe a feature that is no longer supported on these routers as this feature maybe needed for advanced DNS configurations. These are home class routers and are no usually designed around having advanced configurations for the average home class user.

I recommend that you phone contact your regional D-Link support office and ask for help and information regarding this. We find that phone contact has better immediate results over using email.
Let us know how it goes please.

Same issue here with my DIR-850L.  The workaround I have is to use the DHCP service on my Windows 2008 server and disable it all together on the 850L.  This bug should definitely be looked into.