ALTA Gateway Data Logging
Monnit ALTA Gateways offer the ability to receive and retain sensor data upon loss of communication to Monnit software. If a gateway remains powered on and has an established connection to sensors, the gateway’s radio and sensor network will remain active, and the gateway will log and retain the sensor messages that are received during the network downtime. These sensor messages will be subsequently uploaded to the Monnit server in batches.
Note: Logged messages are not supported when operating with the Serial MODBUS Gateway or the MODBUS TCP/SNMP Interfaces of the Ethernet Gateway.
Gateway Limits (varies based on sensor type)
ALTA Ethernet Gateway 4: Up to 50,000 sensor messages
ALTA 4G LTE Gateway: Up to 50,000 sensor messages
ALTA 2G/3G Gateways: Up to 50,000 sensor messages
ALTA USB Wireless Sensor Adapter: 14,336 up messages (to gateway/server) 2,048 down messages (to sensors)
ALTA Ethernet Gateway 3: Up to 16,000 sensor messages
ALTA Serial MODBUS Gateway: Not applicable; data logging not supported
ALTA Advanced Edge Gateway: Not applicable as server is hosted on the gateway
Logged message retention on power loss
The most recent ALTA LTE and Ethernet Gateway 4 firmware versions offer the capability of retaining logged messages upon power loss and delivering those messages upon power restoration and reconnection to the Monnit server. If you are operating with an ALTA LTE or Ethernet Gateway 4 with earlier firmware, your gateway has logged data and loses power, the logged messages will be lost.
ALTA LTE Gateway firmware 220.127.116.11 and later supports logged message retention on power loss.
ALTA Ethernet Gateway 4 firmware 18.104.22.168 and later supports logged message retention on power loss.
Gateway data messages on logged data upload
If your gateway lost a connection to the Monnit server and has retained logged messages, it will deliver those logged messages to the server in batches upon reconnection.
!!Important: If your gateway has been offline for a significant amount of time (days), the time clock on the gateway may have become out of sync with the server clock. This means that when the gateway delivers the logged data, the timestamp may be inaccurate. It is not uncommon to see sensor data delivered with timestamps in the future in relation to the iMonnit server. The time clock will automatically resynchronize with the portal, but the readings will have the offset timestamp.
Disable network on no server on the Ethernet Gateway 4
There may be applications in which you prefer that your gateway does not retain these logged messages during loss of communication to the Monnit server. In applications where loss of network connection is frequent or needs to be carefully monitored, you may want to disable the gateway’s Sensor Network so the sensors log the data instead of the gateway. In this scenario, you can activate the Disable Wireless Network On Server Loss feature of the Ethernet Gateway 4.