While I've never seen it there on a PI, you could check to see if there's a Mango/bin/logs/ directory containing the log file.
Your boot output appears to be a regular boot. Other things that could be affecting what's happening:
- You have a Mango/overrides/classes/log4j2.xml file
- You have moved the debug-logging script from Mango/bin/ext-available to ext-enabled.
I find it strange that your log output has,
Oct 24, 2018 8:24:45 PM com.serotonin.m2m2.db.H2Proxy initializeImpl
INFO: Initializing H2 connection manager
Oct 24, 2018 8:24:49 PM com.serotonin.m2m2.db.upgrade.DBUpgrade checkUpgrade
INFO: Starting instance with core version 3.4.5, db 25
Oct 24, 2018 8:24:49 PM com.serotonin.m2m2.rt.DataSourceGroupInitializer initialize
INFO: Initializing 5 NORMAL priority data sources in 8 threads.
Oct 24, 2018 8:24:56 PM com.serotonin.m2m2.rt.RuntimeManagerImpl initializeDataSourceStartup
Oct 24, 2018 8:25:01 PM com.serotonin.m2m2.rt.DataSourceGroupInitializer initialize
INFO: Initialization of 5 NORMAL priority data sources took 11839ms
Which is anomalous in having a different format than the default, and not logging all the statements that are logged in the default. So, you must have modified your logging configuration. I'd say go back to using the default log4j2.xml file.