[Check_mk (english)] Random errors on nics on ESXi 6.7 hosts

[Jan Krajdl]

Hi,

I have recently upgraded our vSphere cluster with 3 hosts to ESXi 6.7.
At the same time I've upgraded check_mk to 1.5.0p7 raw (previous
version was 1.2.x which isn't compatible with vsphere 6.7). Since
this upgrade I randomly get notifications about errors on vmnic
interfaces on these hosts. Errors are both in and out, appears on
almost all vmnics (included both 10Gbps optical and 1Gbps metalical
nics), appears on all 3 hosts although they have different hardware
(2 hosts is HP DL380 Gen10, 1 host DL360 Gen9). Nothing
shows that these errors are true - no problems on network, everything
works smoothly, in esxcli during problem period no errors at all:

[***@atlas4:~] esxcli network nic stats get -n vmnic4
NIC statistics for vmnic4
Packets received: 15352
Packets sent: 0
Bytes received: 1656369
Bytes sent: 0
Receive packets dropped: 0
Transmit packets dropped: 0
Multicast packets received: 476
Broadcast packets received: 233
Multicast packets sent: 0
Broadcast packets sent: 0
Total receive errors: 0
Receive length errors: 0
Receive over errors: 0
Receive CRC errors: 0
Receive frame errors: 0
Receive FIFO errors: 0
Receive missed errors: 0
Total transmit errors: 0
Transmit aborted errors: 0
Transmit carrier errors: 0
Transmit FIFO errors: 0
Transmit heartbeat errors: 0
Transmit window errors: 0

In same vcenter server I have another small cluster with 2 hosts
running on ESXi 6.5 and I haven't seen any notification about these
hosts.

Is possible there is some different in 6.7 which cause that Check_MK
is bad calculating errors in interfaces?