CradlePoint CTR350 - DNS Poisoning Has Occured

Jim_in_VA · Posted: Fri Jan 11, 2008 6:01 pm Post subject:

I just received that DNS Poisoning message as well from a Cradlepoint pop-up. Along with it was a suggestion to clear the browser cache, close it, and restart the browser. It worked for me.

Jim_in_VA · Posted: Fri Jan 11, 2008 6:09 pm Post subject: DNS Poisoning Has Occurred

This was the message:

DNS Poisoning Has Occurred

Restart your web browser.

It may be necessary to close your web browser and restart it. Sometimes web browsers cache invalid URLs when first logging onto the CradlePoint CTR. Restarting your web browser will clear it's cache and you should be able to surf the Internet without problems.

tvBilly · EVDO User Joined: 02 Dec 2007 Posts: 30

I'm not hooked up to my CTR-350 right now, so I can't double check this, but I seem to remember that when I accidentally tried to connect to the router using the dot 2 address instead of the dot 1 address, I got the poisoned dns screen. In other words, if my CradlePoint was at 192.168.0.1 and I tried to connect to 192.168.0.2 with my browser, I got the error page. I also vaguely remember that the CTR-350 help pages, while explaining the DHCP functions, gave conflicting info in two places. One said that, for example, if your router was set to 192.168.0.1 that you could assign the DHCP to range anywhere between 192.168.0.2 and 192.168.0.254, the other said you could assign between 192.168.0.3 and 192.168.0.254. Note that the second example excludes the dot 2 address.

Not sure if this is relevant or not though...

Bill S

byrd · EVDO User Joined: 21 Dec 2007 Posts: 49

Well, I've confirmed that the ipconfig /flushdns does not work for me. The command line says it was successful, but it doesn't help the problem. Once I'm disconnected, the only solution is a reboot of the router.

Can anyone possibly duplicate this procedure??:

1) Confirm ability to view web pages in browser
2) Go the Cradlepoint Admin>Status page.
3) Confirm that IP Address, Subnet Mask, Default Gateway, Primary DNS Server, and Secondary DNS Server are all set properly.
4) Click "Disconnect", and wait for all server settings to go to 0.0.0.0
5) Click "Connect"
6) See that Primary and Secondary DNS both REMAIN set to 0.0.0.0 after all the other info is updated again.
7) Confirm that web pages can no longer be viewed in a web browser, BUT web sites CAN still be pinged using the command prompt.

What ever is causing my problem seems to essentially be the same thing as manually clicking the "Disconnect" and "Connect" buttons on the Status page. It's just happening on it's own without my intervention.

If someone else is able to repeat this, then at least I might not feel like I'm missing something.

muzicman82 · EVDO User Joined: 13 Dec 2005 Posts: 65

Well, I got the CradlePoint message again today. I took a screenshot, but now the full text is in Jim_in_VA's post.

I can confirm that when I get this message, it is ONLY on my desktop via Ethernet connection. At the same time, my laptop with wifi connection works just fine.

So, it seems like something having to do with the new firmware and it's ability to autodetect uplink? I think perhaps when I pull the card, it then tries to make the Ethernet the uplink for Internet, and then putting the card back in confuses it? Just a theory, but wifi working just doesn't make sense.

Oh, and when I get the message, restarting the browser or clearing cache don't work. I have to power cycle the router. I didn't try flushdns, but what's the point? It's faster to just power cycle if I'm going to have to do something.

The point is, I shouldn't have to do anything.

byrd · EVDO User Joined: 21 Dec 2007 Posts: 49

eastglacierpark · EVDO Newbie Joined: 05 Dec 2007 Posts: 3

CTR-350 Firmware v1.7.1 (2007-11-30)
Sierra AC585U, MC5725 Rev 2.0 (2), p2010002,60610 (8/16/2007)

I'm seeing the same problems, periodically. I was travelling over the holidays in rural Montana where the problem first appeared. I have since returned to Rev.A territory outside Seattle, but the problem persists.

I have encountered the problem with both OpenDNS and the Sprint DNS servers (I usually stick with the Sprint servers as I notice dramatically increased DNS resolution time when I use alternate DNS servers). I do switch occasionally to OpenDNS servers when I hit the ugly "EVDO Connection Fix" issue (which only occurred while roaming in Montana, and only when connected using the CTR-350).

Jim_in_VA · Posted: Sat Jan 12, 2008 5:09 am Post subject:

Oddly, my problem was opposite of Muzicman's. I have a Belkin Pre-N router plugged into the CTR350 and two desktops wired to the Belkin. But I got the poison message on a wireless laptop, not the desktops. I also switched to IE instead of Firefox and did not get the message at all. hmmm....

eastglacierpark · EVDO Newbie Joined: 05 Dec 2007 Posts: 3

All of my poisonings have occurred with IE 7, running under Vista SP1 RC1 (32-bit), Dell E1405 laptop, always with a wireless connection.