and the mouse and keyboard were stuck too.
Looks like the kernel has paniced (crashed), apparently when trying to get statistics from the
tg3 Broadcom NIC driver. You'll need to reset the system to let it reboot again.
You probably should update the system, or at least the kernel, to CentOS 6.[latest] and see if the crash happens again. If you have any third-party driver packages, you should update them too, or re-evaluate if they are still necessary with the latest CentOS 6.x kernel.
The latest CentOS kernels include Spectre/Meltdown fixes, and I've experienced some bad interactions (ranging from annoying "NICs locking up randomly about a week after the system is rebooted" to "100% reproducible crash at boot time") with certain proprietary pre-Spectre/Meltdown drivers when combined with post-Spectre/Meltdown kernels.
You can check any third-party modules using the
modinfo command: if the command
modinfo <module-name> | grep retpoline does not output the line
then the module is from before the Spectre/Meltdown fixes and should probably be updated.