esxi logs will not deleted until the drive is filled. Using syslog you can store all esxi logs into vcenter server. Below link for configuring vcenter syslog
Setting up the ESXi Syslog Collector | VMware vSphere Blog - VMware Blogs
ESXi logs are not deleted, they are rotated every reboot or when reach your maximum size.
Check the following links:
VMware KB: Increasing VMware vCenter Server and VMware ESX/ESXi logging levels
Overview of Configuration Files and Log Files
Hi
can iprevent the log rotate after reboot or shurdown?
Thx