Accessing Cosmos DB with public access disabled and private endpoint configured from Container App

[pkpaul5]

We have container app which accesses Azure Cosmos DB. For security, public access for Cosmos DB has been disabled and private endpoint has been created for Cosmos DB. The container app has been deployed to External Container App environment with same custom VNet as the one used for Cosmos DB private endpoint. The container app is not able access the DB as the outgoing IP of the container app is a dynamic public IP.

I tried to deploy the container app to an Internal container app environment using the same VNet as Cosmos DB private endpoint. Now the app is able to access the DB.

From MS documentation, it is not clear whether the outgoing IP is now a public IP or private IP from VNet. Please let me know.

I have some other container apps in External container app environment with same custom VNet but they are able to access the Cosmos DB with public access disabled and private endpoint configured.