One or more circumstances may apply:
The retention of ESXi Log files is managed based on the volume of Logs generated (File Size & Rotation count) rather than by a specific time period.
1.) Log into the ESXi Host via SSH/Putty
2.) Run the following command to see the current Rotation settings & File Sizes:
esxcli system syslog config logger list
Example Output:[root@ESX:~] esxcli system syslog config logger list Description: vmkernel logs Destination: vmkernel.log ID: vmkernel Rotation Size: 10240 --> Size in KiB. Size of each vmkernel.log will reach ~ 10MB before a new vmkernel.log is being created (rotated) Rotations: 11 --> Total Number of vmkernel logs to keep for ID "vmkernel" before the oldest gets overwritten [root@ESX:~] date; ls -lh /var/run/log/vmkernel*-rw------- 1 root root 389.3K Aug 1 18:46 /var/run/log/vmkernel.0.gz-rw------- 1 root root 564.1K Aug 1 12:32 /var/run/log/vmkernel.1.gz-rw------- 1 root root 538.7K Jul 29 19:24 /var/run/log/vmkernel.2.gz-rw------- 1 root root 550.5K Jul 28 14:02 /var/run/log/vmkernel.3.gz-rw------- 1 root root 551.5K Jul 28 00:26 /var/run/log/vmkernel.4.gz-rw------- 1 root root 552.4K Jul 27 10:52 /var/run/log/vmkernel.5.gz-rw------- 1 root root 554.9K Jul 26 21:18 /var/run/log/vmkernel.6.gz-rw------- 1 root root 553.5K Jul 26 07:47 /var/run/log/vmkernel.7.gz-rw------- 1 root root 553.1K Jul 25 18:17 /var/run/log/vmkernel.8.gz-rw------- 1 root root 555.8K Jul 25 04:46 /var/run/log/vmkernel.9.gz-rw------- 1 root root 1.8M Aug 1 18:55 /var/run/log/vmkernel.log
3.) Identify the ones which consume the most size (= Rotation Size), have a high number of Rotations or for which ID to wish to change the config
4.) Use the following command to adjust
esxcli system syslog config logger set --id=<logger_name> --rotate=## --size=##
Example:esxcli system syslog config logger set --id=vmkernel --rotate=15 --size=8192
5.) Apply the new configuration changes.
esxcli system syslog reload