Telkom LTE and OpenDNS

[netgirl]

Hi all,

I am hoping that someone with more technical expertise than me can assist. I am having issues using OpenDNS with my Telkom LTE network.

All devices have a wireless connection to a new TP-Link Archer MR400 router. I need to blanket block groups of inappropriate website as I have students that use the wireless network during the day. After initial setup with OpenDNS, the blocking of website was working and then for seemingly no reason at all it stopped working.

I noted that the IP address of my PC was changing a few times within a minute. After some research on the forums, I followed the suggestion of other users and created a custom profile on the router interface - using "unrestricted" in the APN field. While this solved the constant changing of IP address issue it is still allowing unfiltered access to websites.

I logged a ticket with OpenDNS and ran the required diagnostic tests. Their feedback was for me to disable ipv6 on my pc. I tried this and still no joy.

I am using OpenDNS successfully on our second ADSL network without any issue.

Any ideas of what the problem can be? Any assistance will be GREATLY appreciated!

 

[PsyWulf]

You don't specify how you actually configured your setup to use OpenDNS,so pretty hard to diagnose what's missing..

 

[sajunky]

I wonder how OpenDNS can cause constant changes of your IP. Most probably you have IP conflict in your LAN. The same regarding changing to unrestricted APN on the WAN side. However such behaviour should take your attention in first place.

 

[netgirl]

You don't specify how you actually configured your setup to use OpenDNS,so pretty hard to diagnose what's missing..

Thanks for the response. Under LAN tab, I enabled DHCP server and entered the two OpenDNS numbers for the primary and secondary DNS fields.

 

[netgirl]

I wonder how OpenDNS can cause constant changes of your IP. Most probably you have IP conflict in your LAN. The same regarding changing to unrestricted APN on the WAN side. However such behaviour should take your attention in first place.

Thanks for the response. I don't think it was OpenDNS that was causing the changes to the IP. I think that is a Telkom issue which I suspected was the cause of OpenDNS not working. The unrestricted APN fixed the changing IP problem, but OpenDNS still is not blocking the websites it should.

I'm not tech savvy at all. How would I go about dealing with a IP conflict in the LAN?

 

[PsyWulf]

Thanks for the response. Under LAN tab, I enabled DHCP server and entered the two OpenDNS numbers for the primary and secondary DNS fields.

Okay,so you have OpenDNS as the DNS,but you didn't specify how you are using the blocking features

Default OpenDNS settings won't block anything,you need an account configured,and the Dynamic DNS client reporting your IP so your connection can be filtered

 

[PsyWulf]

I wonder how OpenDNS can cause constant changes of your IP. Most probably you have IP conflict in your LAN. The same regarding changing to unrestricted APN on the WAN side. However such behaviour should take your attention in first place.

The Rapid "public" IP changes were reported a few weeks ago,telkom implemented some sneaky natting due to public IPs running low. It was most notably affecting gaming and VPNs

 

[netgirl]

Okay,so you have OpenDNS as the DNS,but you didn't specify how you are using the blocking features

Default OpenDNS settings won't block anything,you need an account configured,and the Dynamic DNS client reporting your IP so your connection can be filtered

I have got an account with OpenDNS and have setup two networks - the problematic LTE network and an ADSL network. If I login in to my OpenDNS account it shows the two networks and the IP address associated with each. Both networks are set on customized "high" filtered settings. It appears on the OpenDNS dasboard that both networks are operational, but the blocking only works if my internet connection is via the ADSL network.

I have also downloaded the OpenDNS software on my PC which sends any changes in IP to OpenDNS.

 

[Elax]

DHCP might be giving out the OpenDNS servers, but nothing stops a person on his own pc to override those to something unfiltered, unless you have group policies in place which I doubt.

If you can, set up the router to use OpenDNS and let DHCP point at the router as a dhcp server and block outgoing dns queries in the firewall from the lan network, port 53 I believe

 

[PsyWulf]

I have got an account with OpenDNS and have setup two networks - the problematic LTE network and an ADSL network. If I login in to my OpenDNS account it shows the two networks and the IP address associated with each. Both networks are set on customized "high" filtered settings. It appears on the OpenDNS dasboard that both networks are operational, but the blocking only works if my internet connection is via the ADSL network.

I have also downloaded the OpenDNS software on my PC which sends any changes in IP to OpenDNS.

Are the PCs getting the DNS server settings from the router or is the router using the DNS settings itself and users getting the router as DNS?
You'll have to do some NSLookups to see what IP results are being returned for specific test sites

Also as Elax stated they could just be using their own DNS instead

 

[hackerjargon]

Sounds to me that the workstation gets an dhcp ip from the router and this just bypasses opendns, dns then. One way to turn of dhcp (dhcp on the lan side, not wan side - or you wont have internet) and configure each device manually with a stiatic ip and with opendns as dns servers (208.67.222.222, 208.67.220.220).

Alot of routers, even if you put in custom dns in, will ignor it especially, I've noticed sim card based routers (3G, LTE).

I rather use a linux box (spare pc) configured with pi-hole running and it points to opendns servers (or you can use a raspberry pi instead of a spare pc).
Like I said, test a static ip address and open dns entries with a workstation and see if that works and blocks it then.

 

[netgirl]

Thanks for the assistance everyone. For whatever reason - OpenDNS seems to be working again. Hopefully it will last.

From what I can tell the router is acting as the DHCP server. I am switched back to using the default Telkom dial up settings. I think it is just a mobile broadband issue where sometimes the DNS settings are ignored. I unfortunately can't change DNS settings on connected devices since I am working with 30+ students, not my own children.