6.0.1
Table Of Contents
- vSphere Troubleshooting
- Contents
- About vSphere Troubleshooting
- Updated Information
- Troubleshooting Overview
- Troubleshooting Virtual Machines
- Troubleshooting Fault Tolerant Virtual Machines
- Hardware Virtualization Not Enabled
- Compatible Hosts Not Available for Secondary VM
- Secondary VM on Overcommitted Host Degrades Performance of Primary VM
- Increased Network Latency Observed in FT Virtual Machines
- Some Hosts Are Overloaded with FT Virtual Machines
- Losing Access to FT Metadata Datastore
- Turning On vSphere FT for Powered-On VM Fails
- FT Virtual Machines not Placed or Evacuated by vSphere DRS
- Fault Tolerant Virtual Machine Failovers
- Troubleshooting USB Passthrough Devices
- Recover Orphaned Virtual Machines
- Virtual Machine Does Not Power On After Cloning or Deploying from Template
- Troubleshooting Fault Tolerant Virtual Machines
- Troubleshooting Hosts
- Troubleshooting vSphere HA Host States
- vSphere HA Agent Is in the Agent Unreachable State
- vSphere HA Agent is in the Uninitialized State
- vSphere HA Agent is in the Initialization Error State
- vSphere HA Agent is in the Uninitialization Error State
- vSphere HA Agent is in the Host Failed State
- vSphere HA Agent is in the Network Partitioned State
- vSphere HA Agent is in the Network Isolated State
- Configuration of vSphere HA on Hosts Times Out
- Troubleshooting Auto Deploy
- Auto Deploy TFTP Timeout Error at Boot Time
- Auto Deploy Host Boots with Wrong Configuration
- Host Is Not Redirected to Auto Deploy Server
- Package Warning Message When You Assign an Image Profile to Auto Deploy Host
- Auto Deploy Host with a Built-In USB Flash Drive Does Not Send Coredumps to Local Disk
- Auto Deploy Host Reboots After Five Minutes
- Auto Deploy Host Cannot Contact TFTP Server
- Auto Deploy Host Cannot Retrieve ESXi Image from Auto Deploy Server
- Auto Deploy Host Does Not Get a DHCP Assigned Address
- Auto Deploy Host Does Not Network Boot
- Authentication Token Manipulation Error
- Active Directory Rule Set Error Causes Host Profile Compliance Failure
- Unable to Download VIBs When Using vCenter Server Reverse Proxy
- Troubleshooting vSphere HA Host States
- Troubleshooting vCenter Server and the vSphere Web Client
- Troubleshooting Availability
- Troubleshooting Resource Management
- Troubleshooting Storage DRS
- Storage DRS is Disabled on a Virtual Disk
- Datastore Cannot Enter Maintenance Mode
- Storage DRS Cannot Operate on a Datastore
- Moving Multiple Virtual Machines into a Datastore Cluster Fails
- Storage DRS Generates Fault During Virtual Machine Creation
- Storage DRS is Enabled on a Virtual Machine Deployed from an OVF Template
- Storage DRS Rule Violation Fault Is Displayed Multiple Times
- Storage DRS Rules Not Deleted from Datastore Cluster
- Alternative Storage DRS Placement Recommendations Are Not Generated
- Applying Storage DRS Recommendations Fails
- Troubleshooting Storage I/O Control
- Troubleshooting Storage DRS
- Troubleshooting Storage
- Resolving SAN Storage Display Problems
- Resolving SAN Performance Problems
- Virtual Machines with RDMs Need to Ignore SCSI INQUIRY Cache
- Software iSCSI Adapter Is Enabled When Not Needed
- Failure to Mount NFS Datastores
- VMkernel Log Files Contain SCSI Sense Codes
- Troubleshooting Storage Adapters
- Checking Metadata Consistency with VOMA
- Troubleshooting Flash Devices
- Troubleshooting Virtual Volumes
- Troubleshooting VAIO Filters
- Troubleshooting Networking
- Troubleshooting MAC Address Allocation
- The Conversion to the Enhanced LACP Support Fails
- Unable to Remove a Host from a vSphere Distributed Switch
- Hosts on a vSphere Distributed Switch 5.1 and Later Lose Connectivity to vCenter Server
- Hosts on vSphere Distributed Switch 5.0 and Earlier Lose Connectivity to vCenter Server
- Alarm for Loss of Network Redundancy on a Host
- Virtual Machines Lose Connectivity After Changing the Uplink Failover Order of a Distributed Port Group
- Unable to Add a Physical Adapter to a vSphere Distributed Switch
- Troubleshooting SR-IOV Enabled Workloads
- A Virtual Machine that Runs a VPN Client Causes Denial of Service for Virtual Machines on the Host or Across a vSphere HA Cluster
- Low Throughput for UDP Workloads on Windows Virtual Machines
- Virtual Machines on the Same Distributed Port Group and on Different Hosts Cannot Communicate with Each Other
- Attempt to Power On a Migrated vApp Fails Because the Associated Protocol Profile Is Missing
- Networking Configuration Operation Is Rolled Back and a Host Is Disconnected from vCenter Server
- Troubleshooting Licensing
- Index
Adjust Maximum Queue Depth for Software iSCSI
If you notice unsatisfactory performance for your software iSCSI LUNs, change their maximum queue
depth by running the esxcli commands.
Prerequisites
n
Install vCLI or deploy the vSphere Management Assistant (vMA) virtual machine. See Getting Started
with vSphere Command-Line Interfaces. For troubleshooting, you can run esxcli commands in the ESXi
Shell.
n
In the procedure, the --server=server_name connection option specifies the target server. Be prepared to
enter a user name and password when the target server prompts you. For a list of other possible
connection options, see Getting Started with vSphere Command-Line Interfaces.
Procedure
1 Run the following command:
esxcli --server=server_name system module parameters set -m iscsi_vmk -p
iscsivmk_LunQDepth=value
The iscsivmk_LunQDepth parameter sets the maximum number of outstanding commands, or queue
depth, for each LUN accessed through the software iSCSI adapter. The default value is 128.
2 Reboot your system.
3 Verify your changes by running the
esxcli --server=server_name system module parameters list -m iscsi_vmk command.
The following output shows the queue depth for software iSCSI.
iscsivmk_LunQDepth int 64 Maximum Outstanding Commands Per LUN
CAUTION Setting the queue depth to a value higher than the default can decrease the total number of LUNs
supported.
Change the Outstanding IO Requests Setting
If you adjusted the LUN queue depth, change the Disk.SchedNumReqOutstanding (DSNRO) parameter, so
that its value matches the queue depth. The parameter controls the maximum number of outstanding IO
requests that all virtual machines can issue to the LUN.
Change this parameter only when you have multiple virtual machines active on a LUN. The parameter does
not apply when only one virtual machine is active. In that case, the bandwidth is controlled by the queue
depth of the storage adapter.
The parameter is set per device.
Procedure
1 Enter the following command to display the current DSNRO setting for the specified device:
esxcli storage core device list -d device_ID
The get the output similar to the following:
No of outstanding IOs with competing worlds: 32
2 Change the DSNRO value by entering the following command:
esxcli storage core device set -O | --sched-num-req-outstanding value -d device_ID
Chapter 7 Troubleshooting Storage
VMware, Inc. 65