Hi there @NGJ ! Welcome to Meraki Community 🙂
The bulk creation tool requires serial number of the device as listed in the article "Using the Bulk Network Creation Tool" .
Alternatives are:
1st option is the API Create Organization Network which could be used in a script to bulk create networks without the need of serial number.
2nd option would be the time consuming one. You can pre-create empty networks in the Meraki Dashboard without associating devices yet. While this isn’t "bulk" in the automated sense, it allows you to set up the network structure ahead of time. This would have to done repeatedly a 100x which is definitely not ideal.
Hope this helps!
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