@Saul Nachman - Welcome to Microsoft Q&A and thanks for reaching out to us.
It is possible to use a connection string instead of an instrumentation key. Please find the below doc for more info: https://docs.microsoft.com/en-us/azure/azure-monitor/app/migrate-from-instrumentation-keys-to-connection-strings
This document provides a step-by-step guide to migrate from instrumentation keys to connection strings. It also includes information on prerequisites and migration at scale.
Hope this helps. and please feel free to reach out if you have any further questions.
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