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I am literally throwing my hands up in the air. In ye olde XP days when I used DSL things were as simple as manually inputing a DNS server address and the OS would use that DNS server, but today TWC seems to force override everything in TWC's typical spectacularly bad fashion.

My problem is ever since upgrading to the new TWC modem the DNS Resolution will cut out 1-2 times per week. Internet still functions for things that don't need URL name resolution, but forget anything with URLs. The entire home network is affected. Using the modem's built-in ping tool also resolution fails, so I'm sure it's a problem at TWC's end, not mine. Manually setting my PC to use Google's DNS servers doesn't work as TWC's "connection specific DNS suffix" would override it. I think I figured out how to disable that as it no longer shows inside ipconfig, but even with that change I still can't get Google DNS resolution when it TWC's fails.

Literally the only way to restore DNS name resolution is to power cycle the modem to fix this or wait an unknown length of time for the modem to do whatever it does on its own. The previous TWC modem did this rarely and self-corrected quickly so I can't even give an estimate. I haven't had to do weekly modem resets since the DSL days, short of harassing an unfortunate TWC rep is there anything I can do about this at my end of the network?

Use OpenDNS on your router.

Well the DNS redirection appears to happen at the modem level, as the tech placed a DNS redirect on the modem after the latest DNS failure episode. Also started talking as if it may be a firmware bug in their modem and basically just told me to let them know if it happens again.

TheEmrys wrote:

Use OpenDNS on your router.

TWC overrides DNS settings on the router, same way they override DNS settings on the end user systems.

Kougar wrote:

TWC overrides DNS settings on the router, same way they override DNS settings on the end user systems.

Damn, that sucks. So they actually intercept DNS traffic and direct it to their servers even if you've manually configured your PC to use a statically configured DNS server? If so, that's pretty evil.

"It's evil! Don't touch it!"
http://www.youtube.com/watch?v=F6X9KcrXHwg

Kougar wrote:

Well the DNS redirection appears to happen at the modem level, as the tech placed a DNS redirect on the modem after the latest DNS failure episode. Also started talking as if it may be a firmware bug in their modem and basically just told me to let them know if it happens again.

TWC overrides DNS settings on the router, same way they override DNS settings on the end user systems.

If the modem is also a router I can see this happening. Does TWC allow you to buy your own modem and save $8.00/mo?

JustAnEngineer wrote:

"It's evil! Don't touch it!"
http://www.youtube.com/watch?v=F6X9KcrXHwg

That got a laugh from me.

The Egg wrote:

If the modem is also a router I can see this happening. Does TWC allow you to buy your own modem and save $8.00/mo?

Funny enough you should say that. In order to receive the higher speeds TWC is offering I had to swap out the old modem, even though it was the same model used for 2-3 tiers higher than what I was using. TWC apparently figured out they can save money by keeping oblivious people or those that don't care on their original speed tiers if they can't be bothered to upgrade modems even if the modem has headroom for much more. Unfortunately yes, my new DOCSIS 3 modem is one of those combination modem/routers and doesn't allow manual DNS config. On the old tier I could use my own modem to skip the fee, but on this new one I'm not actually sure. Assuming I can then I'd have to buy a DOCSIS 3 model

My old modem was a normal one and I only infrequently had DNS issues with it. In the past when it acted up I'd try setting my router to Google's DNS servers multiple times whenever it acted up but it never seemed to change anything. ipconfig would always spit this out: "Connection-specific DNS Suffix: satx.rr.com" Still does on with this new setup.

Okay, I may be a bit dense. Nothing worked until I actually entered the IP into the "DNS suffix for this connection" box. None of the settings shown in this dialog panel overrides the DNS suffix except this one single empty box. Ipconfig /all actually shows my DNS changing when I put 8.8.8.8 into it. Voila:

Kougar wrote:

The Egg wrote:

If the modem is also a router I can see this happening. Does TWC allow you to buy your own modem and save $8.00/mo?

Funny enough you should say that. In order to receive the higher speeds TWC is offering I had to swap out the old modem, even though it was the same model used for 2-3 tiers higher than what I was using. TWC apparently figured out they can save money by keeping oblivious people or those that don't care on their original speed tiers if they can't be bothered to upgrade modems even if the modem has headroom for much more. Unfortunately yes, my new DOCSIS 3 modem is one of those combination modem/routers and doesn't allow manual DNS config. On the old tier I could use my own modem to skip the fee, but on this new one I'm not actually sure. Assuming I can then I'd have to buy a DOCSIS 3 model

My old modem was a normal one and I only infrequently had DNS issues with it. In the past when it acted up I'd try setting my router to Google's DNS servers multiple times whenever it acted up but it never seemed to change anything. ipconfig would always spit this out: "Connection-specific DNS Suffix: satx.rr.com" Still does on with this new setup.

My networking knowledge is admittedly very poor, but if your DNS servers are being set at the modem/router level, I would expect whatever you specify further down the line to be moot. Either way, they should have a list of compatible modems for you to view online. Finding a DOCSIS 3.0 model shouldn't be a problem, considering I've been using one since late 2010 (SB6120). Go with an SB6141 if it's on the list.

Kougar wrote:

I'd have to buy a DOCSIS 3 model.

I use this one:
http://www.amazon.com/ARRIS-Motorola-Su ... 00AJHDZSI/
http://www.newegg.com/Product/ProductLi ... ageSize=30

@Kougar - I don't think what you did is valid, AFAIK that box is supposed to contain a domain suffix not an IP. I think you've just managed to confuse Windows' network stack enough that things are working by accident.

just brew it! wrote:

@Kougar - I don't think what you did is valid, AFAIK that box is supposed to contain a domain suffix not an IP. I think you've just managed to confuse Windows' network stack enough that things are working by accident.

Yeah, that's not valid at all.

"Append these DNS suffixes" and "DNS suffix for this connection" are for domain names, like google.com. What's happen is the machine is setting the FQDN to "mypc.8.8.8.8" instead of "mypc.twcdomain.whatever".

You may need to buy a domain name, and use that as the suffix.

The Egg wrote:

My networking knowledge is admittedly very poor, but if your DNS servers are being set at the modem/router level, I would expect whatever you specify further down the line to be moot. Either way, they should have a list of compatible modems for you to view online. Finding a DOCSIS 3.0 model shouldn't be a problem, considering I've been using one since late 2010 (SB6120). Go with an SB6141 if it's on the list.

It's the other way around. Whatever is set on the machine will override whatever is set on the router, or whatever the machine gets from the DHCP server.

The OP has a couple of options here.
1: Set the DNS servers in the DHCP server on the router.
2: Setup an internal recursive DNS server, make the DNS server authoritative for the domain, and an internal DHCP server. Turn off the DHCP server on the TWC router, and run everything off your own server.
3: Get a router that lets the OP control all of that.

I have a mixture of option #2 and option #3. One of these days, I'll switch over to just option #2, but I'll need to get a second server for failover since my router is my backup at the moment. DHCP is the issue, not DNS.

Cox isn't bad. I just run off my own server because I can. The downside is that I opt out of any CDN Cox has, but everything runs quick enough that it's not a problem.

Alright, looks like all of you guys were right. Who'd have figured. Changing the prefix and settings didn't result in any change in the problem after all. I then nuked the Windows adapter settings and restored them to defaults, still without an apparent change. TWC tech looked at the modem settings and claimed he adjusted them, with still no change in the DNS failures necessitating a full modem restart.

I got fed up and replaced the Ubee modem with an Arris SB6183 and after several weeks of use I can safely say there hasn't been a single case of DNS failing to resolve across the entire network, even on default settings. I can only conclude there is a serious firmware bug with TWC provided Ubee modems.

I have an Ubee modem, live in Texas, and use TWC who gave me the modem. I reallllllllllly hope I don't run into this...

just brew it! wrote:

Kougar wrote:

TWC overrides DNS settings on the router, same way they override DNS settings on the end user systems.

Damn, that sucks. So they actually intercept DNS traffic and direct it to their servers even if you've manually configured your PC to use a statically configured DNS server? If so, that's pretty evil.

Not in my area, at least. I can use a custom-configured DNS.

I.S.T. wrote:

I have an Ubee modem, live in Texas, and use TWC who gave me the modem. I reallllllllllly hope I don't run into this...

Mine was a DDW36C, the C meaning for TWC. They do use several different Ubee models.

It happened none one week then three times the next week, so if you've not had any DNS failures loading webpages after owning the thing for a month then you are probably not affected.