How to quickly validate when the last time the Data Repository (Vertica) wrote metric data to the database.

Document ID : KB000010075
Last Modified Date : 14/02/2018
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Introduction:

There may come a time where you question whether the Data Repository is writing data despite showing online.  A time where you could call into question whether the DR is writing data or not would be if you were to not stop a DC before you recover the DR from a backup and not restart the DC once you are done.  In this case everything would show up/green but there would be no data on dashboards.  As reachability is common among nearly all devices we will use that to check the last write time.

Environment:
All currently supported versions of PM (3.0 at the time of writing) and their supported operating systems.
Instructions:
  1. Access a command line on a Data Repository (does not matter which if you are in a clustered environment).
  2. Run the below command where dbpass is equal to the password of the DR admin account:

    vsql -w dbpass -c "select to_timestamp( v.tstamp ) from ( select distinct tstamp from dauser.reach_rate order by tstamp desc limit 10 ) v;"
  3. Results would look similar to the below

 

$ vsql -w dbpass -c "select to_timestamp( v.tstamp ) from ( select distinct tstamp from dauser.reach_rate order by tstamp desc limit 10 ) v;"

    to_timestamp
---------------------
2017-01-11 14:00:00
2017-01-11 13:55:00
2017-01-11 13:50:00
2017-01-11 13:45:00
2017-01-11 13:40:00
2017-01-11 13:35:00
2017-01-11 13:30:00
2017-01-11 13:25:00
2017-01-11 13:20:00
2017-01-11 13:15:00
(10 rows)