Upon the lockloss, we had the same issue with ALS Y not catching any light. I used the same solution as Tony did this morning by restoring the ETMY/ITMY/TMSY sliders to the last time an initial alignment was completed, ~1376843785. After playing with the sliders for a bit once this was restored, I was able to get light on the PD. Being that this is the second time that we have had to restore sliders, perhaps this is evidence of some slow drift (possibly related to the chiller failure) going on at EY? Will investigate this further.

Update:

Was able to catch ALS Y and lock it, but had a few subsequent locklosses following LOCKING ALS. I will try running another initial alignment to see if this helps. ALS Y still had issues catching on IA.

I tried moving ITMY just a hair, flashes would get right below if not at 1 on the LOCKING green arms ndscope template, but when the WFS would turn on it would immediately lose lock. After a few trial and error attempts, I was able to reconcile this by turning OFF the WFS DOF 1/2 Y (found under the EY overview) immediately when they get turned on in ENABLE_WFS. Then, after 5 seconds or so, I would turn ON the WFS DOF 2 Y first, then WFS DOF 1 Y which then allowed the WFS to converge without breaking the lock.

Had to touch SRM by a bit in P for SRC to catch but otherwise the rest of the initial alignment went unaided.

Attached is a 24 hour trend of the witness sensors and slider values for ETM/TMSY and the oplev trends for ETMY. Looking at the scope, I'm not seeing a whole lot of drift of the course of the day, so I'm a bit perplexed why we ran into the same issue again this afternoon, since obviously there's some issue with the Y arm alignment.