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novasource

join:2005-05-16
Dallas, TX

[TWC] TWC DNS servers dont respond after awake from sleep

When I wake a device from sleep, I get no DNS for a few minutes. This is evident by browser errors which specifically finger DNS, by errors logged in Windows's System event log, and by Wireshark, which clearly shows outgoing DNS requests for which there is no response.

If I check ipconfig on my Windows devices, I do see the TWC DNS servers as assigned by DHCP. And my DHCP leases almost always have much more time left, so there's no issue of needing a new lease.

I lean towards this being some issue with TWC because it's happening on multiple devices--not just Windows PCs--and it doesn't happen on other networks.

Has anyone else experienced this?


Jabbu
Premium
join:2002-03-06
Highly doubt its a twc dns issue, if it is, try opendns.

novasource

join:2005-05-16
Dallas, TX
said by Jabbu:

Highly doubt its a twc dns issue, if it is, try opendns.

I mostly agre. The weird thing is I can generally ping the DNS servers even when I'm not getting a response from them.


skuv

@rr.com
reply to novasource
I don't see how you lean to this being a TWC issue. The TWC DNS servers, nor any other DNS servers in existence know that your computer was asleep.

If the TWC DNS servers weren't responding for you, they wouldn't be responding for anyone else at the same time either, and TWC would apparently know about that problem since they'd be getting multiple calls about it.

Wireshark running on the computer that was asleep showing outgoing DNS requests with no response doesn't prove that it's the DNS servers not responding.

If you are testing with more than one machine, and you have one machine that is working with DNS and one that is asleep, then wake it up and it doesn't work, then that's not a TWC DNS problem.

novasource

join:2005-05-16
Dallas, TX
This may not be related to sleep after all.

I have a laptop that has been on for about 10 minutes. I am running Wireshark, and I'm seeing DNS query after DNS query, and rarely do any get a response.

I did where I got a response for DNS on www.dslreports.com, after many tries, but for many other sites, I am just being ignored.


Jabbu
Premium
join:2002-03-06
reply to novasource
Sounds like a router. Plug that laptop directly into the modem, and see if it continues.

novasource

join:2005-05-16
Dallas, TX
We have the TWC-supplied Ubee router/modem.

Are you aware of any configuration on the modem that I can adjust that would be blocking this?

Even when I am getting no response from DNS servers, I still can ping them! So it's like ICMP is being allowed but TCP blocked?


Selenia
Gentoo Convert
Premium
join:2006-09-22
Fort Smith, AR
kudos:2
Step 1: Make sure that Windows is not set to put the network interface to sleep. Known to cause issues, especially behind some routers or with certain network adapters.

Step 2: Tell them to shove that Ubee modem so far up their behinds that it will never see the sun again. They are pure junk and I don't know why TWC started using them so much. They used to use good brands like Motorola and Arris and still do on occasion. Even the old Toshibas were better. Then again, they used to use some terayons in some areas, which are even worse junk. I am cursed with a Ubee modem right now because that's all they had. It gets by somewhat(needs an occasional reboot, gives me full line speed, but worse pings than the good modems, which occasional 1-2 sec dropouts), but is no performer like the Arris I had last time(rock solid) I moved. Other people have the same modem and far more troubles than me. So, I have an insider who will tell me when they get some more Arris modems so I can swap this thing out. If failing that, for some reason, I will consider buying my own. Given the modems are generally junk, having a router built-in is just asking for trouble IMHO.
--
A fool thinks they know everything.

A wise person knows enough to know they couldn't possibly know everything.

There are zealots for every OS, like every religion. They do not represent the majority of users for either.

novasource

join:2005-05-16
Dallas, TX
said by Selenia:

Step 1: Make sure that Windows is not set to put the network interface to sleep. Known to cause issues, especially behind some routers or with certain network adapters.

It's even happening occasionally on my wifi-connected Android phone. I have only default settings on the Windows network adapters, and they work fine everywhere else.

said by Selenia:

Step 2: Tell them to shove that Ubee modem so far up their behinds that it will never see the sun again.

Interesting. I just had my Ubee swapped out 2 days ago, and the DNS problems seemed to get worse.

With the prior Ubee, a DHCP lease renewals fixed the problem. I didn't run Wireshark then, so I am not clear if it was the same problem as now, but now Wireshark now clearly shows DNS non-response for several minutes at a time. Why DHCP lease renewals worked? Beats me! I doubt the new DHCP leases would have specified different DNS servers.

This is really throwing me for a loop, though, because I don't know what specifically in the Ubee would be blocking DHCP responses!


DrDrew
That others may surf
Premium
join:2009-01-28
SoCal
kudos:16
Are you wireless clients set to use the Ubee as a DNS forwarder or are the clients contacting the DNS servers directly?

What are the actual client configured DNS server IPs?

If it's using the default gateway IP as the DNS server IP, then the Ubee is configured as a forwarder and may be crashing randomly. Renewing the DHCP lease my force a restart of that process on the Ubee.
--
If it's important, back it up... twice. Even 99.999% availability isn't enough sometimes.

novasource

join:2005-05-16
Dallas, TX
said by DrDrew:

Are you wireless clients set to use the Ubee as a DNS forwarder or are the clients contacting the DNS servers directly?

I'm not home right now, but DHCP is telling us to use the actual TW DNS servers. The Ubee is not doing its own DNS.

novasource

join:2005-05-16
Dallas, TX
reply to novasource
I just went through the Ubee's settings and noticed something called IP Flood Detection. I was having trouble getting DNS responses, and as soon as I unchecked it, the trouble went away. We'll see if this fixes it.

I couldn't find other cases where run of the mill DNS was being blocked by this, only reports of Torrent-inspired DNS being an issue.


Selenia
Gentoo Convert
Premium
join:2006-09-22
Fort Smith, AR
kudos:2
You are lucky. I can't even access the status page on this piece of junk. TWC has it locked down and I live nowhere near NYC(they are said to do that in NYC) Fortunately, it is a plain modem with no NAT or I would really be crawling up their asses if I could not forward ports. Good job Time Warner Cable assuming the user is an idiot. I am probably smarter than most of your engineers. Anyways I am glad that you got to sort that out. I had issues with an old Linksys router until I disabled that option. So I guess it doesn't always work so well in the midst of port probes which your firewall should take care of anyways, as long as it's configured correctly. Hardening your TCP IP stack can go just as far to protect against the sort of thing(DDoS), anyways. For me it's still a pain in the ass to have to plug in my old bought modem just to see my signal levels. I guess they are like most corporations and want to hide it when they are having an issue.
--
A fool thinks they know everything.

A wise person knows enough to know they couldn't possibly know everything.

There are zealots for every OS, like every religion. They do not represent the majority of users for either.

novasource

join:2005-05-16
Dallas, TX
said by Selenia:

You are lucky. I can't even access the status page on this piece of junk.

Really? Try going to »192.168.0.1 (if you're directly connected), and when prompted to log in, use user for both the username and password.


Selenia
Gentoo Convert
Premium
join:2006-09-22
Fort Smith, AR
kudos:2
Tried it. My Arris responded to 192.168.100.1, which I tried before 192.168.0.1 and 192.168.1.1(just in case). However, this POS doesn't respond to any of the above. 0.1 and 1.1 time right out. 100.1 hangs, which tells me that might be the right address, but TWC did something to disable it.

novasource

join:2005-05-16
Dallas, TX
said by Selenia:

Tried it. My Arris responded to 192.168.100.1, which I tried before 192.168.0.1 and 192.168.1.1(just in case). However, this POS doesn't respond to any of the above. 0.1 and 1.1 time right out. 100.1 hangs, which tells me that might be the right address, but TWC did something to disable it.

Oh, whoops, I have a Ubee, not an Arris.


Selenia
Gentoo Convert
Premium
join:2006-09-22
Fort Smith, AR
kudos:2
I have a Ubee now. I am saying I had an Arris before and did not have these issues, including accessing the status page.


Jabbu
Premium
join:2002-03-06
reply to novasource
That flood protection is terrible.

100.1 usually means the modem is in bridge.
1.1/0.1 is acting as a gateway.

I bet $20 your problem is fixed.

cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:9
reply to novasource
That doesn't work if they've locked the gateway. Our BC service -- Ubee -- is locked. The issue appears to be that there's no "read-only" access for the thing; user/user would give us access to change things, which they really don't want. The previous unstable Arris had separate interfaces for the modem (:80) and router (:8080), so we could see the status without messing with any settings.

While I NEED to be able to see signal levels, they aren't going to give me access to change things just to see the status page. (sucks, and we've called twice because of cable side outages we couldn't see from our end. Luckily, we're calling a tech directly instead of the 30min-on-hold support number -- yes, he told us to do so.)

novasource

join:2005-05-16
Dallas, TX
reply to Jabbu
said by Jabbu:

That flood protection is terrible.

100.1 usually means the modem is in bridge.
1.1/0.1 is acting as a gateway.

I bet $20 your problem is fixed.

I hope it's fixed, but I'm surprised that I cannot find any others reporting this problem! Certainly I'm not the only one who has run into this?


Jabbu
Premium
join:2002-03-06
reply to novasource
It was a big topic sometime in the past, kinda forgot about it to be honest.

nephipower

join:2012-02-20
San Antonio, TX
I while back I used to have the Ubee device and it was a piece of crap. It had all sorts of problems with having packet loss with the ubee router.

I was having intermittent problems with looking my VPN connect for work and all my problems went away when I started using the ubee device in bridge mode and using my own router.

I had a friend who got the same ubee device several months later and started having the same exactly problems. When he changed the ubee device into bridge mode and started using his own router all his problems disappeared too.


Selenia
Gentoo Convert
Premium
join:2006-09-22
Fort Smith, AR
kudos:2
reply to Jabbu
said by Jabbu:

That flood protection is terrible.

100.1 usually means the modem is in bridge.
1.1/0.1 is acting as a gateway.

I bet $20 your problem is fixed.

It must be crappy. With all the port scans I get on TWC(not sure why I didn't get them on Verizon, though TWC is otherwise better), enabling it on my Cisco equipment provides quite a performance boost. My guess is it's not allowing these to flood currently open connections. Of course, if it gets overloaded, I could see it degrading the performance or causing a reboot. I guess that is the difference between crappy and good equipment, among several other factors.
--
A fool thinks they know everything.

A wise person knows enough to know they couldn't possibly know everything.

There are zealots for every OS, like every religion. They do not represent the majority of users for either.