Am 31.03.21 um 09:23 schrieb Klaus Singvogel:
Moritz Kempe wrote:
[...]
I noticed the problem, while i was browsing the internet and got confused
because after a while some domains could not longer be found/connected to by
the browser. (On both, Firefox and Chromium)
I had similar issues, when I changed DNS configuration at my DSL router.
I enabled on my DSL router: TLS for DNS, and, parallel, switched to
public, non-censored DNS servers, as suggested by a large German computer
magazine.
I've done this too. I also activated dns over tls with a privacy dns
server in my router but i haven't mentioned it because it, doesn't
seemed like there was any connection between these changes. On all other
devices this works just fine. And even when i change my dns server to
the default one, the raspberry pi still has these problems. (I tested
this before i wrote the first mail)
Those DNS servers were independent and respect more privacy, compared to
my ISP. But after a while I noticed, that those public DNS servers drop
requests and I saw your error messages at my side too, especially if there
were a lot of name resolutions in a short time period.
On my raspberry pi 400, this could be the case, but on my Debian Stretch
PC it works just fine.
I do experience these issues only on my raspberry pi 400, with both of
my operating systems.
Those errors vanished after a while (several minutes) and everything
worked as expected. But then, when resolving again a lot of domain names,
the issues were back. Especially when I download from S3 Amazon, because
the IP address for s3.[...].amazon.com changes every 10 seconds or so.
On my raspberry pi 400 they occurre and rarely fix themselves but the
majority of these stays up for all eternity (or up to an shutdown).
It don't feels, like you described, it is more like an blocklist which
is getting longer and longer (and forces me to use google when my
favorite search engines are blocked).
Don't know, if both are related.
But my suggestion is to look at your DSL router: if you changed the
defaults for DNS, and, if so, switch back to original, default setting for
testing purpose.
I switched my routers dns server back to the ISPs and also rebootet my
device.
But i wasn't able to get on github.com but at the same time i was able
to get on the by the (German) CUII (Clearingstelle Urheberrecht im
Internet) censored site s.to [0] which shouldn't be accessible because
of the censoring from my ISP.
This worked with both my browsers, firefox and chromium.
Regards,
Klaus.
[0] i do not encourage anyone to watch (illegal) content on s.to, i only
chose this domain to test if i am able to visit censored websites.