Objective: Establish and maintain a supply line for 2 turns.
Turn Limit: 8
Recommended Echelon(s): Any (x2)

A pretty simple supply line map. You only have two venues to lose the supply line here. Your Command Center and the Rally node. Long as you have two echelons ready to chill on them, you'll be fine. (I mean, you should considering this isn't much harder than 1-1 and you needed 3 for that)

Aside from that, just rushing to the Rally node then deploying a second echelon to guard your Command Center on turn 2 is all you really need to know. 

Video of me clearing this map