Since you are extending plain L2 between MX and Ex 3300, you will not be needing any routing.
You can just pass same vlan across meraki mx, ex 4300(mdf) an ex 3300 over trunk ports.
Make sure that, your native vlan id should match between meraki mx and Juniper EX 4300 (MDF).
You can just pass same vlan across meraki mx, ex 4300(mdf) an ex 3300 over trunk ports.
Make sure that, your native vlan id should match between meraki mx and Juniper EX 4300 (MDF).