Use command "vsish -e cat /net/portsets/Dvportset-x/ports/xxxxxx/stats" to check VM vNic port stats and the Tx/Rx drop statistics is increasing.
vmkernel.logIn(182) vmkernel: cpu5:7124623)NetPort: 1890: disabled port 0xxxxxxxxIn(182) vmkernel: cpu3:7124623)NetPort: 1621: enabled port 0x####### with mac xx:xx:xx:xx:xx:xxIn(182) vmkernel: cpu8:7124620)NetPort: 1890: disabled port 0x#######In(182) vmkernel: cpu8:7124620)NetPort: 1621: enabled port 0x####### with mac xx:xx:xx:xx:xx:xxIn(182) vmkernel: cpu23:7124618)Vmxnet3: 12562: There is still packet not transmitted when the device isdisabled, port:0x#######, queue: 0In(182) vmkernel: cpu32:7124622)Vmxnet3: 12562: There is still packet not transmitted when the device isdisabled, port:0x#######, queue: 0In(182) vmkernel: cpu6:7124624)Vmxnet3: 12562: There is still packet not transmitted when the device isdisabled, port:0x#######, queue: 0
vmware.log:In(05) vcpu-5 - VMXNET3 user: Quiesce device 0.In(05) vcpu-5 - Ethernet0 MAC Address: xx:xx:xx:xx:xx:xxIn(05) vcpu-5 - VMXNET3 user: Ethernet0 RSS fields requested by vmx: 3In(05) vcpu-5 - VMXNET3 user: Activate device 0.In(05) vcpu-5 - VMXNET3 user: Ethernet0 Driver Info: version = 24409624 gosBits = 2 gosType = 2, gosVer = 40960, gosMisc = 212In(05) vcpu-5 - VMXNET3 user: Activate request succeeds for device 0.In(05) vcpu-6 - VMXNET3 user: Quiesce device 0.In(05) vcpu-7 - Ethernet0 MAC Address: xx:xx:xx:xx:xx:xxIn(05) vcpu-7 - VMXNET3 user: Ethernet0 RSS fields requested by vmx: 3In(05) vcpu-7 - VMXNET3 user: Activate device 0.In(05) vcpu-7 - VMXNET3 user: Ethernet0 Driver Info: version = 24409624 gosBits = 2 gosType = 2, gosVer = 40960, gosMisc = 212In(05) vcpu-7 - VMXNET3 user: Activate request succeeds for device 0.
VMware vSphere ESXi
The down/up action is trigger from VM guest OS. So contact guest os vendor for further investigation along with Windows event logs, other guest OS related logs.