Hi there for those who might be interested - I also added SNMP/ MODBUS-TCP/RTU functionality configuration through openwrt interface.
to manually add follow these directions
for SNMP
for MODBUS TCP/RTU
you need to update the runfiles dir with this 1runfiles.tar.gz (4.3 MB)
the next bit will be to add in the GPS functionality to the openwrt node via openwrt luci interface- my and goal to make remote nodes act as lowjack using Orange Pi 3G-IOT-B or simular - but also send information from vehicle to influxdb as well