By default we keep traffic metrics in InfluxDB only for 7 days. You may increase or decrease this duration using this guide.
Open command line management interface for InfluxDB:
influx
Then adjust retention using this command:
ALTER RETENTION POLICY "fastnetmon_default_rp" ON "fastnetmon" DURATION 31d DEFAULT
If you prefer to reduce disk usage then approach with removal database and then creation of new database may be better option.
Delete old database (it will remove all data):
drop database fastnetmon
And recreate it with new retention configuration (you can replace 7d by any value):
CREATE DATABASE fastnetmon WITH DURATION 7d REPLICATION 1 NAME fastnetmon_default_rp
After these changes, InfluxDB will remove automatically all metrics older then specified period.
If InfluxDB uses significant amount of disk space, you can follow our guide and suppress data export for hosts.