autosma4@server.auto-smart.net [~]# tail -f /opt/traccar/logs/tracker-server.log
2019-04-30 12:48:13 WARN: One of the protocols is disabled due to port conflict
2019-04-30 12:48:32 INFO: user: 2, action: login
2019-04-30 14:38:37 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 34000800010c0100000000001543061593c22b3b24424e523039423332343538000031392d30342d33302032303a34353a313100
2019-04-30 14:38:37 INFO: Position filtered by Future filters from device: NR09B32458
2019-04-30 14:52:50 INFO: user: 2, action: login
2019-04-30 14:56:41 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 41542b4353510d100000004e52303942
2019-04-30 14:56:42 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 34000800010b050000000000b243741593c21c3c24424e523039423332343538000031392d30342d33302032313a30333a333200
2019-04-30 14:56:42 INFO: Position filtered by Future filters from device: NR09B32458
2019-04-30 14:57:12 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 34000800010c000000000080ac43791593c24d3c24424e523039423332343538000031392d30342d33302032313a30343a303300
2019-04-30 14:57:12 INFO: Position filtered by Future filters from device: NR09B32458
2019-04-30 14:57:43 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 100000004e5230394233323435380000
2019-04-30 14:57:43 DEBUG: [F6EC55D3: 5053 > 216.3.13.179] HEX: 0d0a2a4b57000d000080010d0a
2019-04-30 14:58:02 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 34000800010b07000000000099437d1593c24e3c24424e523039423332343538000031392d30342d33302032313a30343a353300
2019-04-30 14:58:02 INFO: Position filtered by Future filters from device: NR09B32458
2019-04-30 14:58:32 DEBUG: [F6EC55D3: 5053 < 216.3.13.179] HEX: 34000800010c0000000000007442c01493c2913c24424e523039423332343538000031392d30342d33302032313a30353a323300
2019-04-30 14:58:32 INFO: Position filtered by Future filters from device: NR09B32458
You can disable filtering in the config, but it usually indicates an invalid time.
The weird part is that it was working just fine, stopped working after the upgrade in the server to 3.17