The master conlog process on h1conlog2 stopped running this morning after reporting the following errors:

Dec  2 10:06:32 h1conlog2 conlog: ../ecm_cac.cpp: 515: event_handler: pv name: H1:GRD-HPI_ETMY_USERMSG: args.status is not ECA_NORMAL: ca_message: No reasonable data conversion between client and server types: Exiting.
Dec  2 10:06:54 h1conlog2 conlog: ../conlog.cpp: 331: process_cas: Exception: boost: mutex lock failed in pthread_mutex_lock: Invalid argument Exiting.

'No reasonable data conversion between client and server types' is an error message generated by the EPICS channel access library. My first suspicion was that the data type changed, but this does not appear to be the case. 

It has been restarted.