So here is how we do this.
WAN to MX100's.
Thankfully our Comcast and Verizon modems have multiple LAN ports so we connect those to WAN1 and WAN2 on both MX100's. Then we have a virtual IP setup between the two MX100's.
MX100's to Core stack
Port 4 on MX100-1 to Port 1 on Core SW1
Port 5 on MX100-1 to Port 2 on Core SW1
Port 4 on MX100-2 to Port 1 on Core SW2
Port 5 on MX100-2 to Port 2 on Core SW2
EDIT: You don't have to use the port numbers above, I just used them for example purposes.
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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