I appreciate this discussion! Discovered that indeed the Dev/Test license only allows one user login, which is the main admin account. If that admin account is given a username other than 'admin', Splunk will not send alerts. If you cat the passwd file for your instance (cat /opt/splunk/etc/passwd), you'll see your main username listed with a hashed password, and the Administrator defined as 'admin', not as the main admin user. Splunk alerts are sent from the 'admin' administrator account, which apparently will work on a non-dev/test license even if the admin account you set up as something other than 'admin'. Solution: edit the passwd file to change the name of your user account to 'admin', then restart Splunk. Please note, I also discovered if you delete the dev/test license and restart Splunk, Splunk will no longer recognized your admin account unless it is named 'admin'... in fact it will say there are no users for this deployment and won't allow you to log out, add/remove/modify users, etc. Again, the issue can be resolved by updating the passwd file and restarting Splunk.
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