We checked the tagger signal during the access with compton. For the right arm, all channels relevant to tagger are working except for "Rpvdis53 -title "Pileup6: E7WA" scaler7_21/disrplw7 scaler8_21/disrplw7c". Need to fix it next time. For the left arm, the tagger signal was not there when we checked it the first time. Then I traced the signal. By unplugging and plugging back in the signal at several places, we got it back and all the channels are working then. So the mysterious disappearing of the tagger for left arm is still happening. Using a single long cable to connect from the patch pannel to the front rack didn't not solve this problem. It should be some module fanning out the tagger that are functioning abnormally. Need to check in detail during next access.
A copy of this log entry has been emailed to: xiaochao, rom, rsubedi