We’ve encountered several instances where customers attempted to configure the serverless option for their Elastic Pools.

However, serverless is not supported for Elastic Pools. For more information on the Serverless compute tier, please refer to this article: Serverless compute tier for Azure SQL Database 

Serverless is price-performance optimized for single databases with intermittent, unpredictable usage patterns that can afford some delay in compute warm-up after idle usage periods. In contrast, the provisioned compute tier is price-performance optimized for single databases or multiple databases in elastic pools with higher average usage that cannot afford any delay in compute warm-up.

For details on the different service tiers available for Elastic Pools, check out these links:

Resource limits for elastic pools using the vCore purchasing mode: Elastic pool vCore resource limits – Azure SQL Database | Microsoft Learn 
Resource limits for elastic pools using the DTU purchasing model: DTU resource limits elastic pools – Azure SQL Database | Microsoft Learn 

If a customer wishes to utilize the Serverless option, they will need to remove the database from the pool and switch the tier to Serverless.

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