Logstash 7.1.1 not writing last_run in last_run_metadata_path

[Giovanni_Gasparri]

Hello guys! I'm experiencing a problem with logstash 7.1.1 running as a deamon on debian with multiple pipelines.

Despite the fact that record_last_run is true and last_run_metadata_path is specified, no file is saved.
The file is not even found in the home folder of root/logstash user.

I tried to change location and extend permissions but with no luck.
I was searching for this file because I would like to delete this file in order to force logstash to reload an index from scratch. I couldn't find it and therefore I deleted the index on elasticsearch. After a while I found that the entire index was populated again.
I wonder... If logstash is not tracking the last run, does this means that every minute it's going to load all the docs into ElasticSearch?

Any suggestion is welcome. Thank you in advance

[Badger]

It sounds like you are using a jdbc input. Can you show us the input configuration? (With sensitive data like passwords redacted.)

[Giovanni_Gasparri]

Ciao Badger, here a simplified version of the input block.

     input {
         jdbc {
             jdbc_driver_library => "/usr/share/java/mysql-connector-java-8.0.16.jar"
             jdbc_driver_class => "com.mysql.jdbc.Driver"
             jdbc_connection_string => "jdbc:mysql://servername:3306/databasename?useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=true&serverTimezone=UTC&zeroDateTimeBehavior=convertToNull"
             jdbc_user => "username"
             jdbc_password => "password"
             jdbc_paging_enabled => true
             schedule => "*/1 * * * *"
             statement => "SELECT field1,field2,UNIX_TIMESTAMP(timestamp_update) 
    as  tracking_field FROM table where timestamp_update < now() and UNIX_TIMESTAMP(timestamp_update)>:sql_last_value 
    order by timestamp_update asc"
                     use_column_value => true
                     tracking_column => tracking_field
                     tracking_column_type => "numeric"
                     record_last_run => true
                     last_run_metadata_path => "/storage/elk/logstash/run_ordsummary"
                }
            }