Hi JFer,
I hope your day is going well.
(1) If you are moving the MX from one Organization 1 to a New Organization 2 - Yes, the configuration settings will be the default - no configurations - https://documentation.meraki.com/General_Administration/Inventory_and_Devices/Moving_Devices_between...
In general, you could use scripts to download configurations such as - https://www.ifm.net.nz/cookbooks/meraki-backup.html. Unfortunately, Meraki Support Team will not be able to assist with the scripts.
(2) As alemabrahao mentioned, if you replace one MX 1 with another MX 2 in the same network in Org 1 - then, the configuration will be saved in the Meraki Cloud - https://documentation.meraki.com/MX/Other_Topics/MX_Cold_Swap_Replacing_an_Existing_MX_with_a_Differ...
(3) If you replace one MX 1 with another MX 2 in a different network under the same Org 1 - we could possible clone the network -
Keep in mind a that some configuration won't be copied as per the documentation - https://documentation.meraki.com/General_Administration/Organizations_and_Networks/Cloning_Networks_...
If you have any questions, please don't hesitate to contact us.
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