eddiem555's profile

Tutor

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6 Messages

Monday, October 14th, 2013 3:09 AM

How to change the DNS server on the Motorola NVG589 router?

Hello, I recently switch from DSL to U-verse and I was using OpenDNS for web content filtering.  With OpenDNS you just change your router to use the OpenDNS DNS servers, then any device connecting to your network gets filtered.  Now that we switched to Uverse the Uverse router is our main router.  I cannot find any way to override the DNS server served up with DHCP to be OpenDNS servers.   So does anyone know how to change the DNS server given in DHCP requests of the Motorola NVG589 router? I'm running software version 9.1.0h4d38

 


If changing DNS server address in DHCP response is not an option, I guess the other option would be to turn off the DHCP server on the Uverse modem, and bring up another DHCP server on the network where DNS would be configureable.   So if someone could reply on how to disable the DHCP server on the Motorola NVG589 that would help as well.

 

Expert

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9.4K Messages

10 years ago


@RonV wrote:

Now the fun.  Using your own router make sure you set up the DHCP server allocates addresses outside of the range the NVG589 does but it must be on the same subnet as the NVG589.  Also as a safety net you need to assign the same IP address in your routers DHCP server to the MAC addresses of your receivers.  Because you will have two DHCP servers the first to respond wins and we always want to make sure the receivers have their correct IP addresses.  Also you do not want to use the WAN port of your router from this point on.  Only the LAN ports should be used with one of them going directly to the NVG589.  Some routers allow you to turn the WAN port into a LAN port.  This turns off the routing function allows the router to just act as a switch with a DHCP server and a wireless access point.


 

This is an invalid networking configuration.  There is nothing to prevent the IPTV receivers from renewing their DHCP address from your router vice the RG.  Even though this may give them the correct IP address, they will get a different DNS address if you've put that in your router, which will result in the receivers failing to operate correctly.

 

Any subnet on any network must have at most one DHCP server.

 

The proper way to configure this is to run your router in routing mode, and use IP passthrough (Motorola gateways) or DMZPlus (2Wire/Pace gateways) to send all traffic to your router's WAN port.  This will give your router the public outside IP address assigned to the gateway, avoiding double NAT and separating off your network so that you can run your own DHCP server separate from the IPTV receivers.

 

 

Mentor

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26 Messages

10 years ago

It's not a invaldi configuration the U-Verse receivers can get their IP addresses from either the NVG589 router of my router.  The DHCP server  on my router gives the same static DNS entries for the receivers as the NVG589 would have handed out.  There is nohting invalid in a  network configuration where multiple DNS servers support a single subnet as long as the static pools are configured the same and the global pools don't overlap.  Check out the RFC for DHCP.

 

In my home I gave the NVG an address of: 192.168.1.254

The Recivers: 192.168,1.10, 192.168.1,11, 192.168.1,12

The DNS servedby the NVG: 68.94.156.1,68.94.157.1

 

On my DNS server which uses DNSmasq I have the exact configuation:

 

dhcp-option=tag:uverse,6,68.94.156.1,68.94.157.1

dhcp-option=tag:uverse,3,192.168.1.254

dhcp-host=00:1c:ea:eb:d3:ee,set:uverse,192.168.1.10,uverse-dvr,1h

dhcp-host=00:1c:ea:eb:e2:62,set:uverse,192.168.1.11,uverse-br,1h

dhcp-host=00:23:be:07:fc:d8,set:uverse,192.168.1.12,uverse-fr,1h

 

To decode the above lines:

tag - creates a grouping of DNS options

DHCP-option 6 - DNS

DHCP-option 3 - Default Gateway 

DHCP-host - MAC,set,static address,hostame,lease time

 

My other hosts on my network either get IP address from the pool or I have static for them which are not "tag" and the DNS is using openDNS.  This configuration has been running since I upgraded to the NVG and realized that I couldn't turn off the DHCP server like I did in my old RG.

 

Expert

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9.4K Messages

10 years ago

OK, with your situation it will work because you're using a Linux DHCP server that can be configured to hand out different options from different pools based on the MAC address. (This was not clear from your previous post).

However, if someone were to try this using a simpler DHCP server, say one that's built into their home router, this would not work because it can't be configured for multiple pools.

Why avoid the 2nd router with bridge mode? It would seem simpler to set up the network that way, which wouldn't require this type of DHCP configuration.

Tutor

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4 Messages

10 years ago

Can someone please give me the exact step by step instructions to use my Netgear WNDR3800 router behind Motorola NVG589?  I am going to use OpenDNS and not sure how to use IP passthrough mode.

Tutor

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4 Messages

10 years ago

Also, if I disable the WiFi on NVG589, will my uverse boxes still be able to connect?  I am setting up a router behind the NVG589 to use for WiFi connections for all other internet devices.

Community Support

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6.7K Messages

10 years ago

Hi @97Smiths ,

 

Here is a helpful thread on how to configure your NVG589 to work with other devices.

 

Also, you will have no problem disabling the Wireless on the router. The WIreless settings on the router only effect the internet connection, and the wireless for the Receivers are controlled through the wireless access point.

 

-David T

Contributor

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1 Message

10 years ago

RonV, I don't understand why you want to run this kind of setup? It doesn't appear like it allows your dhcp on your personal router to give out opendns IPs.

I have mine setup in pass through mode so that my AirPort Extreme's dhcp can give out opendns IPs.

Contributor

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1 Message

10 years ago

I can confirm that RonV's method works. My setup is a little different. I am not running a separate router behind the NVG. I have a Microsoft Windows Active Directory server running DHCP and DNS integrated. I wanted to let the NVG continue to route/switch, I just wanted my AD server to serve IPs and DNS to my Windows clients so internal DNS was happy. I followed RonV's instructions, with a few modifications and enhancements:

 

  • I noticed that my Wireless Set Top Boxes had two MAC addresses, each requesting an IP. I made sure I had an Allocation for both.
  • Microsoft DHCP server allowed me to create a range of IPs outside the range I was using for STBs on the NVG (Windows DHCP was set to 192.168.1.20-50 and NVG was set to 192.168.1.64-69). So no possible address conflicts and I can tell by the IP what device it is.
  • On the MS DHCP server, I used a Deny Filter on the scope and put the STB/DVR MACs into the deny list. This basically makes sure that my MS DHCP server will never service DHCP addresses to the STB/DVRs.
  • I left the Motorola WAP plugged into the NVG and assigned an Allocation IP from the NVG to it, which keeps it closer to the IPTV action.
  • My plan is to take my own WAP, cable it to the network, broadcast a new/separate SSID, and stop broadcasting the Motorola WAP SSID. Wireless Windows/Android/Apple clients would connect to the new SSID from my WAP, and the STBs would continue to connect to the Motorola. My goal here is to keep IPTV traffic on a different AP from my other clients. Yes, technically they're all on the same network, but they're connected to seperate ports on seperate switches, so I feel better about it Smiley Very Happy

Hope this helps!

Contributor

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1 Message

8 years ago

Hey kyle3tash,

 

Do you experience any slowdowns to your internet speed due to DNS on the Windows server? I am having an issue with a similar setup to yours where the DNS on my domain controller drastically slows down my internet. This didn't start happening until a couple of weeks ago and I have had my setup like this for 3 and a half months. Speed test results are horrible. I do not have TV from AT&T, just internet so I only leased 1 IP from the router. If I turn off DNS or unplug the network cable on the domain controller my speeds sky rocket to normal levels for my package. I contacted AT&T support and they will be sending a tech out as we think there might be something wrong with the NVG589 router DNS. I believe they will replace the router and hopefully that works ( I will find out tomorrow and hope fore the best.)

Tutor

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8 Messages

8 years ago

If UVerse customer prem devices need to use ATT specific DNS servers then the ATT RG/device engineering team should have their design utilize an appropriate (separate) DHCP Vendor Option for their proprietary/nonstandard configuration info for their devices to consume.  

 

This would allow customer flexibility and security (with OpenDNS and other competing future technologies); While also allowing RFC2132 compliance https://tools.ietf.org/html/rfc2132#section-8

 

Once they do this, they can allow customer configuration of DHCP option code 6 (name servers) on the private network.

 

This would reduce customer requirements for so many complex workarounds, reduce additional devices and complexity on prem.  This in turn could reduce ATT cost by simplifying support calls related to these complexities.   

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