IvS how to show PRP related stats counters
Article ID: 400268
Updated On:
Products
Issue/Introduction
Industrial vSwitch (IvS) is for realitime applicatrion like industrial ethernet Profinet that requires low latency forwarding. Parallel Redundancy Protocol (PRP) is used for redundancy in IvS. In the case of RPR issue, you need to understand current status of PRP. This KB article describe how to check the PRP related stats counters.
Environment
4.2.x
Resolution
IvS is running as a vDS inside ESXi host. So you can use the nsxcli command to get the stats of PRP.
In a factory use case of IvS, virtual Programmable Logic Controllers (vPLC) are running on the ESXi host and control the IO devices. RPR is used between the IvS on ESXi and the RPR node that connected with IP devices for maintain redundancy with LAN A and LAN B links.
In the output of the nsxcli -c get ens prp stats node, you can find the MAC addresses of the vPLC with VLAN ID. Each MAC address shows the stats for LAN A and LAN B seperately that realize PRP virtual link (vmnic128). vPLC connected with IvS is a Duall attached node (DAN) in PRP network, so Type fieild shows DAN.
prpRxPkt counter shows recived packet count. You can compare the LAN A link and LAN B traffic using these counters. If there is no drop for the both LAN A and LAN B, the counter should show the same value. rxBytes is the counter for recieved packet bytes.
In RPR network, the sender duplicates the packets and forwards the same packets to LAN A and LAN B. the reciever will select the first arrived packets from ether LAN A or LAN B, and drop the other as duplicated. DupDrop counter shows how many packets are dropped due to this duplication. The increase of the DupDrops counter is normal behavior and it doesn't mean the network failure directly.
Between the two PRP nodes, there are supervior frames for health check of the LAN A and LAN B links. supRxPkts shows how many packets are recieved from the remote PRP node. These counters for LAN A and LAN B should show the same value if there is no network issue.
[root@localhost:~] nsxcli -c get ens prp stats node 0
Fri Feb 21 2025 UTC 14:32:50.307
NodeIdx NodeMAC VlanID Type NodeAge(s) LAN prpRxPkts nonPRPRxPkts rxBytes DupDrops supRxPkts OutOfOrderDrops wrongLANDrops
================================================================================================================================================================
(snip)
XXX1 <MAC Address #1> YYY DAN 30576 lanA 19126714 0 1262364348 3082117 19105 0 0
lanB 19126714 0 1262364348 16044597 19105 0 0
XXX2 <MAC Address #2> YYY DAN 30576 lanA 19124661 0 1262229170 3058002 19105 0 0
lanB 19124661 0 1262229170 16066659 19105 0 0
XXX3 <MAC Address #3> YYY DAN 30576 lanA 19126966 0 1262381528 3248085 19105 0 0
lanB 19126966 0 1262381528 15878881 19105 0 0
XXX4 <MAC Address #4> YYY DAN 30576 lanA 19127974 0 1262447170 3057684 19105 0 0
lanB 19127974 0 1262447170 16070290 19105 0 0
XXX5 <MAC Address #5> YYY DAN 30576 lanA 19127974 0 1262447170 3062831 19105 0 0
lanB 19127974 0 1262447170 16065143 19105 0 0
XXX6 <MAC Address #6> YYY DAN 30576 lanA 19126964 0 1262380930 3081174 19105 0 0
lanB 19126964 0 1262380930 16045790 19105 0 0
XXX7 <MAC Address #7> YYY DAN 30576 lanA 19127976 0 1262447530 3563626 19105 0 0
lanB 19127976 0 1262447530 15564350 19105 0 0
XXX8 <MAC Address #8> YYY DAN 30576 lanA 19126962 0 1262380570 3096169 19105 0 0
lanB 19126962 0 1262380570 16030793 19105 0 0
XXX9 <MAC Address #9> YYY DAN 30576 lanA 19124659 0 1262228572 3099190 19105 0 0
lanB 19124659 0 1262228572 16025469 19105 0 0Feedback
