High pNic error rate detected. Check the host's vSAN performance view for details

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Hello @Nitin Jamadagni Madapura Rajashekhar I hope you are doing well,

While it is natural to correlate the high pNIC error rate with the extreme vCenter latency, these are almost certainly two distinct, isolated behaviors within the Azure VMware Solution environment.

1. The pNIC Error Alarm The "High pNIC error rate detected" warning is a documented known issue within AVS. The physical hosts utilize Mellanox network interfaces, and the vSAN health service occasionally misinterprets standard NIC buffer overflow counters as critical hardware errors. This is purely a cosmetic, informational false positive. Action: You can safely right-click the alarm in the vSphere Client and select "Reset to Green". Microsoft manages the underlying firmware, and no hardware intervention is required.

The Extreme Management Latency Because the pNIC error is cosmetic, it is not the root cause of your vCenter and ESXi access latency. Extreme latency to the management plane in AVS typically points to one of the following constraints:

• ExpressRoute or VPN Gateway Saturation: Check your Azure Monitor metrics for the Virtual Network Gateway to ensure you are not hitting bandwidth or packet-per-second limits on the circuit connecting your on-premises environment to the AVS private cloud.
• NSX-T Edge Congestion: If the management traffic is traversing heavily utilized tier-0/tier-1 gateways, CPU saturation on the Edge nodes can cause severe UI latency.
• vCenter Resource Starvation: Occasionally, the vCenter appliance itself experiences high CPU or memory pressure.

Since you do not have root access to restart the vCenter services or deeply inspect the Edge node operating systems, the recommended path is to immediately open an Azure Support ticket specifically highlighting the management plane latency, rather than the pNIC error.

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