Re: Xen 4.18/ARM64 on Raspberry Pi 4B: VLAN traffic crashing Dom0

[Paul Leiber <paul@xxxxxxxxxxxxxxxx>]

On 16.09.2023 13:26, reijo.korhonen@xxxxxxxxx wrote:
> On Thu, 2023-09-07 at 18:41 +0200, Paul Leiber wrote:
> > However, as soon as I remotely access the zabbix web interface, the
> >
> > complete system (DomUs and Dom0) becomes unresponsive and reboots
> > after
> >
> > a couple of seconds. This is reliably reproducable.
> >
> >
> >
> > I didn't see any error message in any log (zabbix, DomU syslog, Dom0
> >
> > syslog) except for the following lines immediately before the system
> >
> > reboots on the Xen serial console:
> >
> >
> >
> > (XEN) Watchdog timer fired for domain 0
> >
> > (XEN) Hardware Dom0 shutdown: watchdog rebooting machine
> Hmm.. Here you have a hint, how to study this issue. Seems, that this
> is not Xe, issue, but it is watchdog issue. Your should set watchdog to
> log, why it is rebooting machine.
>
> You can also set or edit watchdog to do something else than rebooting
> machine, because rebooting does not help your study.
I tried to dig deeper into the cause for the watchdog triggering. 
However, I didn't find any useful documentation on the web on how the 
watchdog works or how to enable logging. Can anybody direct me to useful 
information on the Xen watchdog, please?
> Maybe it could also be helpful set your system to pure VLAN system
> without Xen at all, but set system somehow to run same kind apps your
> run with Xen and zabbix web interface. Maybe running Web server is
> enough to study your VLAN1 and VLAN2. When your are sure, that VLAN1
> and VLAN2 settings are OK and VLAN itself work with Raspberry OK, it is
> much easier to continue with Xen and zabbix.
I booted the system without Xen and set it up to use the VLAN 20 bridge 
(the same that leads to a reboot when using it in the DomU) as primary 
network interface. Everything seems to be working, I could download 
large files from the internet without any problem. Next step is then to 
follow your advice reproduce the Zabbix setup (sigh).
Paul