This section contains issues related to virtual or physical network connectivity within Proxmox.
Network connectivity issues
Issue – no connectivity on Realtek RTL8111/8411 rev. 06 network interfaces
Some newer Realtek chipsets don't get compiled with the right drivers. This causes the interface to be up without any network traffic. In order to fix this issue, the older driver needs to be downloaded from the Realtek site and compiled manually. The driver can be downloaded from http://www.realtek.com.tw/Downloads/.
Since this driver is manually installed, during a kernel update it will get updated automatically. To prevent this and ensure that the driver builds itself automatically when a new kernel is installed...