Hi @rui dias , welcome to Microsoft Q&A forum.
It seems you are not able to locate pgbouncer in server parameters in Azure PostgreSQL server.
If you have created Azure PostgreSQL - Single Server, this parameter is not available. You can check this as mentioned in below screenshot with yellow highlighted box:
PGBouncer is available as a built-in option for Azure Database for PostgreSQL – Flexible Server. It is supported on General Purpose and Memory Optimized compute tiers in both public access and private access networking.
As mentioned in the below screenshot it is available:
PgBouncer in Azure Database for PostgreSQL - Flexible Server
Please let us know if this helps or else we can discuss further on the same.
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