ESXi host HBAs offline

Products

• VMware vSphere ESXi

Issue/Introduction

The administrator observes vCenter alarm for errors stating "Path redundancy to storage degraded". 

Alarm alarm.StorageConnectivityAlarm on Host
hostame.domain.###
         because
         Path redundancy to storage device naa.################################ degraded. Path vmhba#:C#:T#:L# is down. Affected datastores: <datastore_name>..

Environment

vSphere - ESXi and vCenter (all versions)

Cause

Connectivity between the ESXi host and storage array is lost due to failure outside of the ESXi host.

ATS miscompare log messages coupled with vmfs heartbeat timeout messages indicate extreme latency was being experienced prior to the path loss. These messages originate from latency and communication failures originating outside of ESXi.

vmkernel logs:

2025-03-30T23:22:03.269Z cpu77:2098305)NMP: nmp_ThrottleLogForDevice:3867: Cmd 0x89 (0x45d9edb97888, 2099392) to dev "naa.#################################" on path "vmhba2:C0:T1:L4" Failed:
2025-03-30T23:22:03.269Z cpu77:2098305)NMP: nmp_ThrottleLogForDevice:3875: H:0x0 D:0x2 P:0x0 Valid sense data: 0xe 0x1d 0x0. Act:NONE. cmdId.initiator=0x430975e901c0 CmdSN 0xe1f12
2025-03-30T23:22:03.269Z cpu77:2098305)ScsiDeviceIO: 4115: Cmd(0x45d9edad5288) 0xfe, CmdSN 0xe1f12 from world 2099392 to dev "naa.#################################" failed H:0x0 D:0x2 P:0x5
2025-03-30T23:22:03.269Z cpu55:2099392)DLX: 5465: vol 'datastore_name1', lock at 278417408: Lock type: 10C00001. [Req mode 1] try lock error: Atomic test and set of disk block returned false for equality:

Resolution

Reboot the host to restore connectivity.
Discuss with host hardware, fabric, or storage array vendor for cause of communication problems between ESXi and LUNs.

Additional Information

Validate all data path components on the host are on the compatibility guide with the correct drivers and firmware.