Using ESXCLI to Troubleshoot VMkernel Storage Module Configurations

This VCAP-DCA objective appears to be to do with storage hardware such as HBAs and the drivers/modules that ESXi uses to interface with them. To start with, you can list the storage adaperts installed in a ESXi host by running:

~ # esxcli storage core adapter list
HBA Name  Driver     Link State  UID                                    Description
--------  ---------  ----------  -------------------------------------  --------------------------------------------------------------------------------
vmhba0    ata_piix   link-n/a    ide.vmhba0                             (0:0:7.1) Intel Corporation PIIX4 for 430TX/440BX/MX IDE Controller
vmhba1    mptspi     link-n/a    pscsi.vmhba1                           (0:0:16.0) LSI Logic / Symbios Logic 53c1030 PCI-X Fusion-MPT Dual Ultra320 SCSI
vmhba32   ata_piix   link-n/a    ide.vmhba32                            (0:0:7.1) Intel Corporation PIIX4 for 430TX/440BX/MX IDE Controller
vmhba33   iscsi_vmk  online      iqn.1998-01.com.vmware:esxi1-47be1f31  iSCSI Software Adapter

In this example, I only have the iSCSI software adapter in use (vmhba33), but if you had physical HBAs you would see them here. You can see stats for the adapter by running:

~ # esxcli storage core adapter stats get
vmhba33
   Successful Commands: 1288
   Blocks Read: 67936
   Blocks Written: 58
   Read Operations: 711
   Write Operations: 58
   Reserve Operations: 15
   Reservation Conflicts: 0
   Failed Commands: 65
   Failed Blocks Read: 0
   Failed Blocks Written: 0
   Failed Read Operations: 0
   Failed Write Operations: 0
   Failed Reserve Operations: 0
   Total Splits: 0
   PAE Commands: 0

In terms of troubleshooting, you should pay attention to any of the ‘failed’ counters, as anything other than a zero here may indicate a problem. You can perform a storage rescan for either a specified adapter, or all adapters by running:

~ # esxcli storage core adapter rescan --all

Getting a List of Installed VMKernel Modules

You can list the installed VMkernel modules, which include storage related modules, by running:

~ # esxcli system module list
Name                 Is Loaded  Is Enabled
-------------------  ---------  ----------
vmkernel                  true        true
procfs                    true        true
vmkplexer                 true        true
vmklinux_9                true        true
vmklinux_9_2_0_0          true        true
random                    true        true
dm                        true        true
nmp                       true        true
vmw_satp_local            true        true
vmw_satp_default_aa       true        true
vmw_psp_lib               true        true
vmw_psp_fixed             true        true
vmw_psp_rr                true        true
vmw_psp_mru               true        true
.....

For example, we can see that the nmp module and the psp modules are installed and enabled.

Useful Links and Resources

https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1017588