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Monday, 22 December 2014

Format of the ESXi 5.x vmksummary log file (2004566)


This article provides information about the format of the ESXi 5.x vmksummary.log file.
Note: This article pertains to ESXi 5.x. For information about other versions, see Heartbeat messages in an ESX /var/log/vmksummary log file (1009016).


The ESXi 5.x log file /var/log/vmksummary.log contains information regarding ESXi host startup and shutdown, and an hourly heartbeat with uptime and other metrics.

Startup and Shutdown

The vmksummary.log file contains bootstop messages indicating startup and shutdown of the ESXi host. For example:
  • yyyy-mm-ddThh:mm:ssZ bootstop: Host has booted
  • yyyy-mm-ddThh:mm:ssZ bootstop: Host is rebooting
  • yyyy-mm-ddThh:mm:ssZ bootstop: Host is powering off
  • yyyy-mm-ddThh:mm:ssZ bootstop: Host is halting

Hourly Heartbeats

Every hour, a heartbeat message is written to the vmksummary log. This information can be useful to indicate the liveliness of the ESXi host and its logging, or to review virtual machine quantities or component memory usage over time.
  • yyyy-mm-ddThh:mm:ssZ heartbeat: up UPTIME, NNN VMs; [memory leaderboards]
Memory usage leader boards show the three userworld processes on ESXi which have the highest resident, non-swapped memory usage:
  • Absolute usage measured in kilobytes: [PID ProcessName nnnkB]
  • Usage as a percentage of maximum allocation for the group: [PID ProcessName nnn%max]

    Note: Process names are truncated to 16 characters.
For example:
  • 2011-08-30T04:00:01Z heartbeat: up 0d17h24m17s, 0 VMs; [[3411 sfcb-pycim 12516kB] [3041 vpxa-worker 12668kB] [2723 hostd-worker 33844kB]] [[3348 sfcb-vmware_int 2%max] [3423 sfcb-vmware_bas 5%max] [3411 sfcb-pycim 16%max]]

Coredump Reporting

During ESXi host startup following a purple diagnostic screen, the host checks for new contents in the configured Diagnostic Partition on disk. For more information, see Collecting diagnostic information from an ESX or ESXi host that experiences a purple diagnostic screen (1004128)and Configuring an ESX/ESXi host to capture a VMkernel coredump from a purple diagnostic screen (1000328).
  • yyyy-mm-ddThh:mm:ssZ bootstop: Core dump found