Turns out that this service is responsible for the Content Library and Transfer services. When you look for the service within the vSphere web client you won't find it listed under a friendly name but rather by the "vdcs" abbreviation (the full name is com.vmware.vdcs.cls-main).
ERROR | wrapper | 2016/08/22 19:28:26 | 4728 pid file, var/log/vmware/vdcs/vm ware-vdcs.pid, already exists.
FATAL | wrapper | 2016/08/22 19:28:26 | ERROR: Could not write pid file /var/l og/vmware/vdcs/vmware-vdcs.pid: Inappropriate ioctl for device
ps -ef | grep vmware-vdcs
to make sure that process isn't running. And then I backup the current PID file, delete it and start the vdcs service:
And give it 5 minutes for vR Ops to check on things. My error is now cleared!
Fortunately, I have vR Ops to report this - otherwise I would not have known that this service was down until I needed it to be up!