Ref WP#3489

Prior to this work, EY H2 Coil drivers were disabled to prevent any damage occuring to ETMY and TMSY (Vern Sandberg and Jim Batch).

Various H2 front ends were rebooted by Alex. The failure of all front end data as detected by the DAQ data concentrator was eventually reproduced, along with the spontaneous crash of h2dc0 when the front end recovered.

Alex spent most of the day with the H2 DAQ down while he tried various upgrades to the MX_STREAMS drivers and code on the concentrator. 

By 4pm the H2 DAQ was returned to operational. At around the same time the H1 DAQ was restarted with a complete set of VACUUM and FMCS channels, so that when the H2 DAQ is taken down over the weekend these channels will continue to be trended.

Alex will continue this work through to Monday. The aim is that the bug whereby a single front end restart/reboot  invalidates all front ends data for many minutes at a time will be resolved.