aLIGO LHO Logbook

H1 DAQ (CDS)

david.barker@LIGO.ORG - posted 18:20, Thursday 06 October 2016 - last comment - 10:28, Friday 07 October 2016(30291)

DAQ nds saw a corrupted frame file from h1fw1, problem is in the NFS exporting/mounting of this file

Jonathan, Jim, Dan, Dave

Jim W reported data errors from 06:14PDT this morning in the full frame. We found that the commissioning frame file for this time is correct on the LDAS QFS file system, but corrupt when NFS exported by the h1ldasgw2 NFS server machine to the nds machines. This is a relatively new solaris server installed this summer to take read-only exports away from h1ldasgw0 when h1fw0 was unstable.

I've opened an FRS for this #6370

Investigation is continuing, including a full characterization of the problem.

Comments related to this report

jonathan.hanks@LIGO.ORG - 18:25, Thursday 06 October 2016 (30292)

Link

I have a new build of daqd frame writer running h1fw2.  Now when we write raw frame files we also write a checksum file next to the file.

This will give us a view of what the daqd says was written out so that LDAS/DCS can verify they receive the file CDS produces.

Tomorrow I will do this on the trend files, and reflect some of this information into EPICS so that we can get a graphical alert when frame writers produce different output.

jonathan.hanks@LIGO.ORG - 10:28, Friday 07 October 2016 (30302)

Link

I now have a build of daqd frame writer running on h1fw2 (and the test stand) that provides checksum files for all frames being written.

In addition it adds four EPICS channels that give 32bits of the checksum to help with medm monitors for Dave.

Prefix each with IFO:DAQ-FW[012]_ (in general, currently only deployed for H1:DAQ-FW2_)

FRAME_CHECK_SUM_TRUNC

SCIENCE_FRAME_CHECK_SUM_TRUNC

SECOND_FRAME_CHECK_SUM_TRUNC

MINUTE_FRAME_CHECK_SUM_TRUNC