New Ubuntu/Xen host/guest combos seem to work perfectly except for a lack of host to guest ethernet traffic flow.
I create xen hosts and guests using the default/routine commands/processes and get the result of no ethernet traffic flow from the host to the guest as each pings the other.
Comparing the output of a number of trouble shooting commands on this machine to the same commands on a machine that works perfectly, the following two discrepancies are the only differences that I have been able to identify.
1/. Monitoring both the host bridge xenbr0 and the guest eth0 with tcpdump as the guest pings the host shows that Arp packets transit from guest to host with the responses visible on the host xenbr0 but not on the guest eth0 interface.
2/. Similarly the command
## brctl showmacs xenbr0
provides the expected output, however the 00:16:3e:xx:xx:xx addresses of the guests are missing.
A bit of detail of host/guest creation.
I create a new Xen host by creating an install usb key from Ubuntu.com/download/server and then run
## apt-get install xen-hypervisor-amd64 etc
which results in a host machine that seems to me to operate as usual.
Similarly I create guests using
## xen-create-image onto lvm with settings to allocate a fixed ip address to the guest.
Again the guest seems to operate as normal when accessed using via
## xl console guest
Some detail on the systems
Host and guest of the failing system are running netplan and the mobo is Asrock J3160 Itx. I’ve tried the possible combinations of Ubuntu 20.04, 22.04, host and guest including a known good guest on both a 20.04 and a 22.04 host. Results of each test the same (as far as I can tell).
I’ve valued Ubuntu/Xen for more than a decade. Rebuilds have “just worked”. I am now seeking tools/help to trouble shoot and resolve this issue.