I am using a kvm ubuntu 10.04 virtual machine to test some features of a kernel module. I grep through the `/var/log` files to observe the kernel messages about that module.

To start from a clean state, I remove log files containing older messages by executing `rm -rf /var/log/*` and then rebooting the virtual machine. However, after I reboot, the new log files still contain those old log messages. It takes about 5-6 cycles of deleting files and rebooting virtual machine to finally get rid of those log file messages.

Why is this happening?
Is there an easier way to cleanup log files?