Steps to reproduce:

1. By default network support for VMs under Proxmox use VirtIO as the model.

Result:

1. When using the Linux by Zabbix agent active the speed of the network interface is shown as an error, showing -1000000
2. Changing the network model from VirtIO to VMXNET3 solves the problem.

Expected:

1. When using the Linux by Zabbix agent active the speed of The network interface is shown as an error, showing -1000000