Re: Networking in Qemu with Xilinx-zcu102 machine

[Berto Furth]

Hi Asif,

It looks like your guest OS is in a different IP subnet than your virbr0 interface.

The host virbr0 is using 192.168.122.1/255.255.255.0 but the guest seems to have 192.168.1.2/255.255.255.0 (Notice the 3rd octet is different)

Can you see what happens if you setup the guest as 192.168.122.2 or something like that?

If that makes no difference then would you be inclined to run a traffic sniffer on the host for virbr0 in another window while the guest and host try to ping each other?

Something like

tcpdump -e -i virbr0

Or maybe even something like this to just get traffic from the guest in case there's too much output

tcpdump -e -i virbr0 ether host 00:0a:35:02:78:10

Thanks Asif!

Berto.

On Wed, 9 Jun 2021, at 03:09, asif siddiqui wrote:

Hello All,

I am working on the networking between my host OS linux and guest OS QNX(Running on top of qemu). I have an interface xzynq0 in my guest OS with a static/dynamic IP address. 

I am executing the qemu command as follows - 

qemu-system-aarch64 -M xlnx-zcu102 -m 8G -serial mon:stdio -display none -device loader,file=QNX_IFS.bin,cpu-num=0 -netdev bridge,br=virbr0,id=net0,helper=/usr/lib/qemu/qemu-bridge-helper -nographic  -global xlnx,zynqmp-boot.cpu-num=0 -global xlnx,zynqmp-boot.use-pmufw=true

 

But the observation is when i try to ping the guest OS with some IP from my host OS, it is showing destination unreachable or when i try to ping from my guest to host it shows host is down. 

I do have a virbr0 bridge in my host os - 

virbr0    Link encap:Ethernet  HWaddr 00:00:00:00:00:00  

          inet addr:192.168.122.1  Bcast:192.168.122.255  Mask:255.255.255.0

          UP BROADCAST MULTICAST  MTU:1500  Metric:1

          RX packets:0 errors:0 dropped:0 overruns:0 frame:0

          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000

          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B) 

And in my guest OS the interface is - 

xzynq0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500

address: 00:0a:35:02:78:10

media: Ethernet 100baseTX full-duplex

status: active

inet 192.168.1.2 netmask 0xffffff00 broadcast 192.168.1.255

inet6 fe80::20a:35ff:fe02:7810%xzynq0 prefixlen 64 scopeid 0x11

Can you please help me out here what am i missing to enable the networking. Is it the case that bridge is not getting set correctly ? Or what can be the possible reasons for the same ? 

Regards

Asif