We keep a spare switch and MX on hand to avoid downtime waiting for the RMA device (even though Meraki is very fast). If it is the same model as what you are replacing then you don't need a license. If it isn't then you get 30 days before you have to get a license so it'll still work fine as a spare until you get your RMA device.
Adam R MS | CISSP, CISM, VCP, MCITP, CCNP, ITILv3, CMNO
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