FreeBSD clock frozen

OS : FreeBSD 8.2

Hypervisor: VMware ESXi 5.0


The clock on our FreeBSD webserver suddenly stopped. This appears to be a bug in in ESXi 5.0.

To fix this:

If the time counter is using HPET then change this to ACPI

sysctl kern.timecounter.hardware=ACPI-safe

Note: The setting doesn't persist after a reboot so make sure you put the following line in /etc/sysctl.conf


Edit: VMware have actually released a patch for this: KB:2021185