Search


DASWG LAL Doxygen

Docs

How-To's
Technical
Software Docs
Minutes

Download

Browse CVS, Git, or SVN
Software Repositories
OS Security Updates
LIGO software virtual machine
VMware SL6 Install

Participate

SCCB - Software Change Control Board
Edit these pages
Sub-committees
Mailing List
Telecon

Projects

DMT
DQSEGDB
Glue
GraceDB
gstlal
LALSuite
LDAS Tools
LDG Client/Server
LDR
ligoDV
LIGOtools
LVAlert Administration
LVAlert
MatApps
Metaio
NDS Client
PyLAL
LSCSOFT VM

Legacy Projects

geopp
LDAS
LDM
LIGOtools
LSCGIS
Onasys
OSG-LIGO

Checking the status of the database and replication

Publication and Server Status

An overview of the publishing status is given by the LIGO Publishing Script Status page. This available from LHO or LLO:

The pages mirror each other, so the information should be the same at either site. The status lights relevant to the segment database are

DMT DQ segment publication status

John, please write something that explains how to check that the DMT is successfully publishing DQ segments and what to do if there is a failure.

Replication Status

Basic publication and replication checks

The easiest way to check the status of replication is to query the database at the site and see if real time frames are being replicated. To do this

The creator_db number is 1 for LHO, 2 for LLO and 3 for CIT. For each segment number that appears check the time of the segment against the current time. If the last segments are less than around 10 minutes old, then replication is working.

We illustrate the procedure with an example at LHO:

[ldbd@ldas.ldas-wa ~]$ db2 connect to seg_lho
   Database Connection Information

 Database server        = DB2/SUN 8.2.3
 SQL authorization ID   = LDBD
 Local database alias   = SEG_LHO

[ldbd@ldas.ldas-wa ~]$ db2 "select creator_db,end_time from segment order by end_time desc fetch first 10 rows only for read only"

CREATOR_DB  END_TIME   
----------- -----------
          1   825962752
          1   825962752
          1   825962720
          1   825962720
          1   825962688
          1   825962688
          2   825962656
          1   825962656
          1   825962656
          2   825962644

  10 record(s) selected.

[ldbd@ldas.ldas-wa ~]$ date
Thu Mar  9 10:06:38 PST 2006
[ldbd@ldas.ldas-wa ~]$ tconvert -l 825962752
Mar 09 2006 10:05:38 PST
[ldbd@ldas.ldas-wa ~]$ tconvert -l 825962656
Mar 09 2006 10:04:02 PST

In this case, the lastest segment from LHO is 1 minute old, indicating that local publishing is working, and the latest segment from LLO is 2 mintes old, indicating that publishing is working at LLO and replication from LLO to LHO is active.

Where to look next if segments are not appearing

If local publishing is functioning at both sites, but segments are not being replicated between sites, then check the pages created by the IBM Data Propagator Q-replication analyzer. This is run at midnight on each site and dumps the status of the replication engine at each sile onto a web page:

Check these pages for error or warning messages and follow the instructions in the toubleshooting pages to diagnose and correct errors.

$Id$