systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system.
The key commands or arguments you will use with systemctl are the following:
list-units [PATTERN...] List loaded units
#if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used
tar -jxvf ffmpeg-3.3.2.tar.bz2
install prefix /usr/local
source path  ........
heartbeat is stopped for some reason
Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow.
Here is the last log I see of heartbeat:
Sep 9 17:15:32 hnode2 heartbeat: : info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL]
Sep 9 17:15:32 hnode2 heartbeat: : info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL]
Sep 9 17:15:32........