[OdroidC1] no names resolution + kernel update issues

[kernelpanix]

Hi there,

I have some issues with my Odrdoid C1:
1/ I have trouble getting name resolution to work properly. In fact, each time I reboot I cant resolve external domains. I have to mess around with systemd-resolved and dhcpcd by stopping, starting, and restarting them until it finally works... Enabled services match those on other working installations (RPi, Odroid n2, etc.) and my /etc/resolv.conf is exactly the same I get on all my other installations...

2/ I can't boot when installing linux-armv7-odroidc1 thus I am stuck with linux-odroid-c1

Any ideas?

[summers]

May try some of the ideas on the can't get internet working thread that's been active last few days. In particular is your clock syronised. $this->bbcode_second_pass_code('', 'timedatectl status') should say.

[kernelpanix]

Thanks, actually changing the timezone seemed to do the trick... I'll see if it persists.

Regarding the kernel, I have actually no way to see what happens: there is no hdmi output, just a black screen and logs are totally empty. To me, nothing happens!

[windozupdat3]

As far as I know, unfortunately, HDMI output is not yet supported on C1 mainline kernel: http://linux-meson.com/doku.php

[summers]

Timezones shouldn't affect the time syncronisation needed for DNSSEC.

Guess it could have been that the systemd ntp was just slowly drifting the time to achieve syncronsation, rather than doing a big jump at start up. It one thing I havn't been able to find any documentation on, what systemd does with time on startup ...

[kernelpanix]

$this->bbcode_second_pass_quote('windozupdat3', 'A')s far as I know, unfortunately, HDMI output is not yet supported on C1 mainline kernel: http://linux-meson.com/doku.php

[summers]

hirtdasi - are you have the same DNS problems as others? Not clear from your post.

Many people on arm boards have been having DNS problems recently. It isn't yet completely clear why, but many of the problems seem to be because the recent release of systemd has the default DNSSEC setting as "allow-downgrade". You can see this by:
$this->bbcode_second_pass_code('', 'resolvectl status
Link 3 (wlp3s0)
Current Scopes: DNS LLMNR/IPv4 LLMNR/IPv6
DefaultRoute setting: yes
LLMNR setting: yes
MulticastDNS setting: no
DNSOverTLS setting: no
DNSSEC setting: allow-downgrade
DNSSEC supported: yes
Current DNS Server: 192.168.2.1
DNS Servers: 192.168.2.1
fd84:32c:ad2f::1
')
So it only seems to be a problem if you are using a recent systemd, and systemd-resolved - resolvectl will confirm.

Now the problem only seems to affect some, I don't have any problems on any of my machine, but they all as above have DNS point to 192.168.2.1 which is my router. What the theory is, is that machines that don't have a RTC, on first boot come up with a wrong time. Usually this is solved via NTP to remote host, but DNSSEC look up when clocks aren't aligned, seems to fail hard. This means the name of the NTP server can't be looked up, and so time can't be syncronised. This may be why my set up works - my router will have my NTP server in its cache, so probably always gets the IP address to syncronise to.

So, hirtdasi, does this apply to you? Is it the problem you are having?

[windozupdat3]

$this->bbcode_second_pass_quote('kernelpanix', '[')
I'm using it only through ssh for server applications so I don't mind having hdmi working. Does it mean I need to disable hdmi in my boot.ini to make it work?

[kernelpanix]

Thanks, I'll look at it, I think this is the problem I'm facing on kernel upgrade.