How to set up mikrotik for 2 providers, one of which is yota from another mikrotik?

Question

Yota

Good afternoon.
There was a need for a fault-tolerant Internet, based on Mikrotik equipment. There are a lot of instructions on the Internet on how to do this, but I couldn’t find a solution for my task anywhere, there are:
1. The main Mikrotik router, which includes wired Internet from the provider, let’s call it ISP
1 a usb whistle with a yota sim card is inserted - let's call it ISP 2
There is no possibility to directly insert the modem into the main router, because it is far from the window, and in that room it does not catch the connection well.
Therefore, in order for the signal to be as strong as possible and the ISP2 router appears
, the connection scheme seems to be approximately as follows
- The ISP1 router both worked and works, it has five ports, eth1 - ISP1, eth2 - lan, eth3 - ISP2
- From the ISP2 router, the cable goes directly from the eth2 port to the ISP1 router and is inserted into the eth3 port
I tried the following implementation schemes to Internet appeared on the ISP1 router from the ISP2 router:
1. Set the address on the ISP2 eth2 router 10.10.0.1/24, on the ISP1 eth3 router 10.10.0.10/24 - does not work
2. Raised the dhcp server on the ISP2 router, configured nat if you connect a local PC, then there is Internet, if you connect a dhcp client on the ISP1 router - it does not work.
Tell me, please, what is missing in my scheme, and how can I solve a similar problem?

Answer 1

You didn't read the instructions. Come back after reading.
https://wiki.mikrotik.com/wiki/Advanced_Routing_Fa...