vSAN resync is not completing... performance issues with VMs... RDMA is enabled

Products

• VMware vSphere ESXi

Issue/Introduction

vSAN resync is not completing.

Performance issues with VMs

RDMA is enabled

vmkernel.log
------------------

2025-12-01T20:32:36.304Z In(182) vmkernel: cpu57:2098705)RDT: RDTRDMAConnectionSendMbufTo:5396: connection in error
2025-12-01T20:32:36Z In(182) vmkernel:
2025-12-01T20:32:36.304Z In(182) vmkernel: cpu57:2098705)RDT: RDTRDMAConnectionSendMbufTo:5396: connection in error
2025-12-01T20:32:36Z In(182) vmkernel:

Environment

vSAN 8.x

Cause

RDMA enabled on the cluster

Resolution

Check if RDMA is enabled. Follow below to disable RDMA: 

Disable RDMA from the vSphere UI through the below steps
Select cluster object: Configure > Services > Network > RDMA support (edit)