On an ESXi host system there a number of log files that can be used for troubleshooting, which contain configuration and operational errors as well as performance information. Some of the most important ESXi log files are listed as below. In order to view the log file this can be performed at the ESXi shell running a utility to view files such as tail which allows for changes to the file to be viewed as they are written to the log file. Alternatively, you can also log directly onto the ESXi host system using the vSphere Client to view the log files.
| Log File | Description |
| /var/log/auth.log | ESXi shell authentication success and failure |
| /var/log/dhclient.log | DHCP client logs, includes discovery, address lease, requests and renewals |
| /var/log/esxupdate.log | ESXi pathches and update installation logs |
| /var/log/hostd.log | Host management service logs includes virtual machine and host tasks and events, communication with the vSphere client and vCenter Server vpxa agent and SDK connections |
| /var/log/shell.lo | Contains a history of all commands that have been run on the host |
| /var/log/sysboot.log | VMkernel statup and module loading |
| /var/log/boot.gz | Compressed file containing boot log information |
| /var/log/syslog.log | Management service initialization, watch dogs, scheduled tasks and DCUI use |
| /var/log/usb.log | USB device events, such as discovery and pass-through to virtual machines |
| /var/log/vob.log | VMkernel observation events |
| /var/log/vmkernel.log | Core VMkernel logs, includes device discovery, storage and networking device and driver events and virtual machine startup |
| /var/log/vmkwarning.log | VMkernel warning and alert log messages |
| /var/log/vmksummary.log | Summary of ESXi host startup and shutdown and hourly heartbeat with uptime, number of virtual machines running and service resource consumption |
The vCenter Server system log files can be located by browsing to ‘C:\ProgramData\VMware\VMware VirtualCenter\Logs’ to which the following log files contain data to perform troubleshooting.
| Log File | Description |
| vpxd.log | Communication data between the vCenter Server Agent (vpxa) on the ESXi host system |
| vpsx-profiler | Operational and performance counters used to profile vCenter Server operation. |
| \drmdump\clusternnn\ | DRS actions grouped by DRS cluster. The log files are gzipped. |
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