How to organize a small, fault-tolerant VPN network?

Question

linux

Guys, I set myself the task of organizing a small network at the enterprise, I would like to hear advice on equipment! Since the experience itself has little, so as not to re-assemble the rake, we
need a fault-tolerant VPN network, a central router, and 5-6 client routers connect to it. Well, something like this, I imagine it, on the central router there are 2 providers + 1usb flash drive with a cellular provider. At remote points 1 provider +1 flash drive in case of failures. Fault tolerance means that if the main provider falls, then the branch will be able to work through the usb modem!
So, please advise the equipment! I hope you can do without cisco here, since the budget is limited, I know that mikrotiks are good, but I would like to hear some specific models! Or maybe you can do without network equipment and raise Linux gateways, but this option seems to me not very successful. I want to do the right way

Answer 1

@VitonZizu what will be the load on the network? Give me more introductory information...
one of the inhabitants of toster sent me to mikrotik + ospf, helped me with the launch, now I'm in awe, now there is already a network of 4 points,

Answer 2

Indeed, we need scale.
once did this
in the CO ROUTERBOARD 1100AHX2 3 providers
in the branch if up to 10 computers ROUTERBOARD 951UI-2HND 1-2 providers (2-3 vpn to the CO and one to the neighboring branch)
more than 10, but less than 40 RouterBOARD 2011UiAS-RM 2 provider (2-3 vpn to the central office and one to the neighboring branch)
+ ospf dynamic routing
If you need help, contacting

Answer 3

Announce budget and workload. And also what is proposed to include in Mikrotik.
So something from RB951 or RB2011 is possible