virtualbox.org

Hello!
OpenSuse 15.1 as Host
Windows 10 64bit as guest
VirtualBox and ExtensionPack version 6.0.14 r133895 (Qt5.9.7)

After guest starts ~ 5 seconds, host machine losts network - no pings to default gateway, but it can ping itself
After reboot host network is ok.

When I change network settings on Virtual machine to NAT -host network is alive

Do you have any idea?

Are you connected to a company network?
Then your switch port may be configured to just allow a single MAC address, ask your network administrator.

Thank You for answer!
Yes I connected to a company network. I asked network admin - switch allows 2 MAC addresses

When I start VM with NAT everything is ok.
And if I change to bridged network, i cant ping host from another computer. Network stops after this

2019-12-04T11:48:49.891533+03:00 kadrf3 kernel: [77948.627919] VBoxNetFlt: attached to 'eth0' / 78:ac:c0:c4:05:20
2019-12-04T11:48:49.905451+03:00 kadrf3 kernel: [77948.635278] device eth0 entered promiscuous mode

The network switch of your company disables your network port when it "sees" the virtual machine network address.
Your network administrator needs to look into it why.

Thank You very much! Our security admins blocks inregistered mac address.
Now problem is solved! You are my hero I spend a week with this problem

rustemka71 wrote:I spend a week with this problem

You could have simply asked 'Martin' for the solution...
Marking as [Resolved].