I'm going to take a different strategy. Ask the ISP performing the upgrade whether they can provide a pair of SFP+ ports in a bridge configuration to connect the primary and backup firewalls. It will be easier for you if they take this on. If they are not keen, ask them what they would charge to provide this service. Otherwise, I think the MS130-24X is the lowest spec Meraki switch that has 4 SFP+ ports (you need three ports). https://documentation.meraki.com/Switching/MS_-_Switches/Product_Information/Overviews_and_Datasheets/MS130_Datasheet Also, do you have a 10Gbe connection between the MX95 and your 6509?
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