Questions on some functionality of RAK7249

Issue:
I am currently evaluating the D4+ RAK7244C and Edge Max RAK7249 to see which one can suit my needs. I like the Edge Max because it’s IP67 ready, 16 channels and has an optional backup battery. My gateways will be deployed in rural areas where LTE is patchy and the whole system is powered by solar. I cannot rely on the Cloud so I have a local node-red server connected through LAN dealing with downlinks to my nodes. My data is then periodically sent to the cloud from the node-red server whenever Internet connectivity is available. I have 2 questions which I can’t seem to find a definite answer to from the other forum posts that I have gone through.

  1. Can I run a local node-red server on the Edge Max as this is possible with the Raspian based D4+?

  2. If no.1 is not possible, and I use a locally connected node-red server hosted on a RPi, can I share the Edge Max’s LTE connection with the RPi?

Thanks.

Not official answers, but some thoughts from a user / modifier of similar systems.

That’s going to be extremely challenging. If you are okay with the system simply going down during most of the night when you get a stretch of short winter days that all turn out overcast, it might be a little easier than trying to make sure you have enough battery to get through a stretch of low insolation days and then enough panel to recharge it before you get hit again. If using a pi based solution, you need a battery controller that can actually command a shutdown, the openwrt gateways are a bit more robust against unexpected power loss though it’s still not a great idea to do so without warning, particularly if they are running an on-board LoRaWAN server stack (a traditional LoRaWAN gateway reporting to a cloud stack doesn’t have any local network state it needs to preserve, only the integrity of its software to worry about).

  1. Can I run a local node-red server on the Edge Max as this is possible with the Raspian based D4+?

I would doubt that’s an official capability. Practically, if you can get a compact enough setup and build it with the mt7628 openwrt 15.05 cross toolchain, possibly. But that would be an expert level project entirely outside of the supported, intended use of the box.

  1. If no.1 is not possible, and I use a locally connected node-red server hosted on a RPi, can I share the Edge Max’s LTE connection with the RPi?

In theory the openwrt operating system can be configured by an expert in that to do this (it’s meant for routers after all) but I don’t know that it’s offered as an intended and supported capability of the gateway product. I’d probably put the modem on the custom system instead and have it provide an Ethernet connection to the gateway. But two computers are going to increase your power consumption and the number of places where something can go wrong.

Thanks @cstratton for the insights.

To clarify, this will not be an issue where I am at in South East Asia but enough batteries will be put in to take into account rainy days. Also good idea about the battery controller. I will have to see if one is available here or not.

Thanks. I would have hope that it’s possible since 2 other gateway brands I had tested have this feature built-in although not running an updated version of node-red. As for building it with the mt7628 that is beyond what I can do at this point in time.

I was thinking the height of the gateway on top of a pole would help with the LTE signal strength if the use case is possible. The custom system would probably sit lower to facilitate maintainability.

From your replies, I think most probably I will test with the D4+ since I can host everything on-board and see if running the LoRaWAN stack as well as the node-red server together will be too taxing for the gateway.