How to organize a backup channel with small forces?

Question

mobile connection

Good day, please help. With the advent of a new remote warehouse in the organization, the following task arose.
The warehouse network is connected to the organization's general network through a "router", a server and "pptp" (a network based on MS solutions with "Active directory"), but the problem is that the warehouse is located in a very geographically remote area (it takes more than two days), the main channel-link to the warehouse network is regularly unstable, the warehouse employees are exclusively "unskilled workers", the closet with the equipment is locked for security reasons, it is not possible to instruct anyone to approach the equipment. From the warehouse server from time to time it is necessary to take data, indicators from the equipment,
It is extremely necessary to organize a backup communication channel to the organization's network "with little bloodshed". As a "little blood" an old nettop with a 3g modem is planned, why a nettop? On its basis, it is planned to later place some necessary software (python scripts for generating cases with various data). The question arises of how to do this so that, as far as possible, the channel through the mobile connection is always there, on the basis of which it would be easier for us if the nettop with win7 automatically connected via 3G and pptp to our server, we would manage the warehouse through rdp. But the question arises, how is this possible and will it look like in the event of a long blackout, after power is supplied, the nettop will turn on, boot up, and then? because the user is not authorized in the system in any way, if there is no main channel, how to automatically force a usb modem to "ring" without user authorization. The second solution is to put ubuntu or any other distribution on the nettop, but it also has questions, automatic dialing via mobile modem and pptp, and also the question of accessing resources on the network with active directory from Linux.
What would you recommend based on this information?

Answer 1

If you follow your idea of ​​"little blood" to the end. A netbook with a screen off without electricity can really work for 4-5 hours, without any special tambourines. UPS - another 3 hours can be screwed on. In total, 8 hours of work without light is a minimum (actually more). I understand that the soul asks for automation and versatility, but such a decision can be made tomorrow.

Answer 2

I'm leaning towards the solution on ubunte
www.thefanclub.co.za/how-to/how-auto-connect-ubunt...
there is no netbook, there is a nettop.

Answer 3

Perhaps I'm missing something, but isn't it easier to use routers with multi-WAN and USB support, for example, ZyXEL Keenetic or some Asus models, where you can insert, respectively, a USB modem that will act as a backup channel?
We made such a decision, however, the remote office was not so far away and a Yota modem was inserted into the router as a backup.

Answer 4

we thought, to be honest, we don’t know what the routes to and from the network will look like (we didn’t do this), and I would like some more software to run on the nettop.

Answer 5

Connecting from Ubuntu to a network with AD is done by Samba, there will be no problems here.
The backup channel can be raised when the main one crashes using the svn1.sytes.net/fallback-gw/ utility or any self-written crutch in 10 lines.