ESXi Storage Showing as NaN%, Workload inside ESXi impacted.

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms : 

• The ESXi host is currently unresponsive and unable to execute commands, indicating it is in a hung state. Running any command for example, df -h via a putty session results in the Host becoming unresponsive.
  
  
• While restarting the ESXi host temporarily resolves the issue, the host eventually returns to the hung state after some time.
  
  
• Unable to manage the ESXi hosts and its datatsore is in inaccessible state. 

Environment

VMware vCenter Server 7.x  
VMware vCenter Server 8.x

Cause

Device READ CAPACITY IO failure on the ESXi host resulted in the host getting into a hung state.

Example:

There are frequent 'READ CAPACITY' errors observed for "naa.xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" when the host was in a hung state.

/var/log/vmkernel.log has logging similar to: 

2025-04-02T08:49:18.918Z cpu1:2100577 opID=cb91ed41)WARNING: ScsiDeviceIO: 12146: READ CAPACITY on device "naa.62cea7f0b096e60028784d291735b1e0"
2025-04-02T08:49:18.918Z cpu1:2100577 opID=cb91ed41)WARNING: ScsiDeviceIO: 12146: READ CAPACITY on device "naa.62cea7f0b096e60028784d291735b1e0"
2025-04-02T08:49:18.918Z cpu1:2100577 opID=cb91ed41)WARNING: ScsiDeviceIO: 12146: READ CAPACITY on device "naa.62cea7f0b096e60028784d291735b1e0"
2025-04-02T08:49:18.918Z cpu1:2100577 opID=cb91ed41)WARNING: ScsiDeviceIO: 12146: READ CAPACITY on device "naa.62cea7f0b096e60028784d291735b1e0"

Resolution

Please refer to the fix mentioned in KB # 387516