Ever since I rebooted my system a week ago both of my OpenVZ VMs are reporting a constant system.uptime of 0, even when they have been running for 5+ days. Have tried rebooting both the agent and the VM. Cannot reboot the physical box as there are other critical services running on it. Using zabbix_get from the site's proxy reports a system.uptime of 0 but other values are working correctly. Running 'uptime' from the command prompt gives me the correct output. I don't understand why it stopped working. Please help.