Re: Sporadic DNS failure

From: Sreenath Battalahalli <sreenathbh_at_rocketmail.com>
Date: Fri, 15 Mar 2024 04:13:10 UTC
 
Hi Chris,

Thanks for your message.
The wifi continues to be associated with access point, and I can ping 1.1.1.1 as well.
My USB wifi interface is rtwn(earlier urtwn)

It is just that DNS queries fail, even when 1.1.1.1 is accessible, at least to ping.

Is it possible that UDP communication is failing? 
Is there any log information that can shed more light on the issue?

thanks,
Sreenath

     On Friday, March 15, 2024 at 12:48:47 AM GMT+5:30, Chris <bsd-lists@bsdforge.com> wrote:  
 
 On 2024-03-14 00:12, Sreenath Battalahalli wrote:
> Hi,
> 
> I have been using freebsd as my primary OS on my ACER laptop for many years 
> now.
> My laptop has 802.11AC card for which there is no kernel driver available. I 
> am I
> use a USB wifi adapter to access the wifi router.
> 
> I am having sporadic DNS failures .
> 
> After reboot, everything works fine but after some time (30 minutes to a 
> couple of
> hours), Internet
> connections start to fail.
> 
> When this happens, I am able to ping 1.1.1.1, my DNS server.
> 
> However,
> # drill yahoo.com (or any other name) fails with following error:
> 
> Error: error sending query: Could not send or receive, because of network 
> error
> 
> Other devices connected to same Wifi router continue to work fine.
> 
> I ran drill under truss and it appears after sendto to 1.1.1.1, no response 
> comes.
> 
> After this error occurs, it stays like that for many some time (20-30 
> minutes) and
> sometimes it gets resolved by itself.
> 
> 
> #uname -a
> FreeBSD bsd12 13.0-RELEASE-p13 FreeBSD 13.0-RELEASE-p13 #0: Mon Aug 29 
> 19:52:47
> UTC 2022    root@amd64-builder.d
> aemonology.net:/usr/obj/usr/src/amd64.amd64/sys
> /GENERIC  amd64
> 
> Can someone please help me debug this problem?
I'm going to suggest that this might be a symptom of your usb port/hub 
hanging-up/
disconnecting due to inactivity. Your BIOS setup may have a setting 
associated
with that. OTOH I don't know what NIC driver you're using for your USB 
network
adapter. When you discover you can't perform DNS lookups, are you still 
associated?
eg; does the output of ifconfig still show associated? What are the settings
in rc.conf(5) related to your network setup?
> 
> Thanks,
> Sreenath

HTH

--Chris