Hi.
The data size will be roughly the same.
If it’s just that you need to see that the configuration is in effect check the output of the https://docs.mongodb.com/manual/reference/method/db.serverCmdLineOpts/ mongo shell command. If the data-at-rest settings are present (security.enableEncryption: true being the main one) it must be in effect - the mongod would have aborted on startup if it couldn’t follow those settings.
And if you look in the https://docs.mongodb.com/manual/reference/method/db.collection.stats/index.html for any collection then in the “wiredTiger.creationString” field I believe you will see one of the WiredTiger table options is something about encryption (“encryption=(keyid=identifier)”)
If you don’t want to take it on faith that the configuration information is true, then there’s a strong practical test you can do. Comment out the the security.* settings for encryption in the mongod.conf file and restart to observe that it cannot recover the data without the encryption keys. Disclaimer: I don’t know if this will cause damage or not. I am suggesting it now only because it sounds like you’re trying in a dev environment for the first time.
Akira
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