Troubleshooting storage issues when using VMware products

Products

• VMware vSphere ESXi

Issue/Introduction

When using storage hardware in a virtualized environment, it is very important that the hardware remains in a healthy state as it is the backbone of the environment. Without reliable storage, a virtualized environment can experience erratic behavior or even a catastrophic failure. This article attempts to assist on troubleshooting when experiencing any of these issues:

• Slow performance
• Unpredictable failures
• Disk corruption, or virtual machine corruption
• Alerts or alarms being received
• Need to know best practices on how to properly set up and maintain an environment
• Not enough storage space to install required resources

Environment

VMware vSphere ESXi

Resolution

To maintain a healthy environment and troubleshoot the above issues, VMware recommends the following resources and articles.

Best Practices and Informational

• Minimum required permissions for Storage VMotion
• Tuning ESXi for better storage performance by modifying the maximum I/O block size
• Guidelines for Microsoft Clustering on vSphere
• Testing virtual machine storage I/O performance for ESXi
• Overview of virtual machine snapshots in vSphere
• Considerations for using software iSCSI port binding in ESXi

How to

• Changing a LUN to use a different Path Selection Policy (PSP)
• Determining Network/Storage firmware and driver version in ESXi

Storage vMotion issues

• Using Storage vMotion to migrate a virtual machine with many disks fails with timeout

Snapshot issues

• Virtual machine becomes unresponsive or inactive when taking memory snapshot
• Unable to use Snapshots or perform a backup on virtual machines configured with bus-sharing

Local storage issues

• Troubleshooting poor local storage controller performance for VMware ESXi/ESX

Microsoft Clustering issues

• Microsoft Cluster Service (MSCS) support on ESXi
• ESXi host takes a long time to start during rescan of RDM LUNs

Storage arrays

• "state in doubt; requested fast path state update" error in ESXi
• Physical drive failure on a storage array
• Cannot see some or all storage devices in VMware vCenter Server
• Unable to mount NFS datastore from NetApp storage array due to incorrect configuration
• Troubleshooting fibre channel storage connectivity
• VMware ESXi hosts in All-Paths-Down (APD) condition may appear as Not Responding in VMware vCenter Server
• Permanent Device Loss (PDL) and All-Paths-Down (APD) in vSphere ESXI
• Identifying Fibre Channel, iSCSI, and NFS storage issues on ESXi hosts
• ESX/ESXi hosts might experience read or write performance issues with certain iSCSI storage arrays

General Storage troubleshooting

• Troubleshooting the Add Storage Wizard error: Unable to read partition information from this disk
• Lost or degraded connectivity to storage device
• Linux based file systems become read-only
• "The parent virtual disk has been modified since the child was created" error
• Troubleshooting ESXi connectivity to iSCSI arrays using software initiators

General storage resources

• VMware product documentation at the VMware Documentation site
• Ensure the hardware is compatible and at the proper firmware level by checking the VMware Compatibility Guide
• Discuss the issue with others who may have experience the same issue at Broadcom Communities
• In depth detail and white papers at the VMware Technical Resource Center
• Collecting diagnostic information for VMware products
• Location of log files for Broadcom products