Re: [Qemu-devel] [PATCH V2] net/traffic-mirror:Add traffic-mirror

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Li Zhijian (lizhijian@cn.fujitsu.com) wrote:
> 
> 
> On 02/01/2016 10:57 AM, Jason Wang wrote:
> >
> >
> >On 01/29/2016 09:38 AM, Li Zhijian wrote:
> >>
> >>
> >>On 01/28/2016 01:44 PM, Jason Wang wrote:
> >>>
> >>>
> >>>On 01/27/2016 10:40 AM, Zhang Chen wrote:
> >>>>From: ZhangChen <zhangchen.fnst@cn.fujitsu.com>
> >>>>
> >>>>Traffic-mirror is a netfilter plugin.
> >>>>It gives qemu the ability to copy and mirror guest's
> >>>>net packet. we output packet to chardev.
> >>>>
> >>>>usage:
> >>>>
> >>>>-netdev tap,id=hn0
> >>>>-chardev socket,id=mirror0,host=ip_primary,port=X,server,nowait
> >>>>-traffic-mirror,id=m0,netdev=hn0,queue=tx/rx/all,outdev=mirror0
> >>>>
> >>>>Signed-off-by: ZhangChen <zhangchen.fnst@cn.fujitsu.com>
> >>>>Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
> >>>>Reviewed-by: Yang Hongyang <hongyang.yang@easystack.cn>
> >>>
> >>>Thanks for the patch. Several questions:
> >>>
> >>>- I'm curious about how the patch was tested? Simple setup e.g:
> >>>
> >>>-netdev tap,id=hn0 -device virtio-net-pci,netdev=hn0 -chardev
> >>>socket,id=c0,host=localhost,port=4444,server,nowait -object
> >>>traffic-mirror,netdev=hn0,outdev=c0,id=f0 -netdev
> >>>socket,id=s0,connect=127.0.0.1:4444 -device e1000,netdev=s0
> >>>
> 
> a strange thing is about "host=localhost", connection is refused at SUSE 11.3 but
> connection is connected successfully at Ubuntu 15.10 if i launch qemu with the
> command line above.
> I try to launch qemu at three physical machines installed with SUSE 11.3, they all
> connect failed. But when I specified "host=127.0.0.1", the connection is OK.
> 
> I have comfirmed that:
> - "localhost have pointed to 127.0.0.1 if I "ping localhost" at SUSE
> - "telnet localhost 4444" works at SUSE

My guess is that it's IPv6 related; check the /etc/hosts so see if there's
a ::1 entry for localhost; I've seen some weird behaviour on rhel in the
same way but in other uses.

Dave

> 
> >>>does not works for me.
> >>Hi， Jason
> >>
> >>I just test the mirror using the command line above, it don't work too.
> >>I am looking to it, and find that seems because the -net socket
> >>problem that
> >>I have ever post a patch  try to fix（refer to ↓）
> >>[Qemu-devel] [PATCH] report a error message if -net socket can not
> >>connect to server
> >>https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg00758.html
> >
> >Will have a look at this.
> >
> >>
> >>after applying this patch, the qemu monitor tell me following message:
> >>(qemu) qemu-system-x86_64: net socket is not connected Connection refused
> >
> >Maybe two issues. Have you tired to start the mirror on one VM and then
> >using socket backend to connect it from another VM?
> 
> Yes, if i connect the mirror on VM1 using socket backend from another VM2, the connection
> is established successfully. But on VM2 guest, I can't dump any packet using 'tcpdump'
> That's because in current version code, mirror is not compatible with socket backend and
> we will fix it in next version.
> 
> 
> Best regards.
> Li Zhijian
> 
> >
> >>
> >>
> >>Thanks
> >>Li Zhijian
> >>
> >>
> >>
> >
> >
> >
> >.
> >
> 
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK