sharing penpals between dedicated SMTP server and MX servers pool

Hello,

I'm using @work a dedicated SMTP server with Amavisd-new and a Redis backend. I'm also using a pool of 3 MX servers each one using Amavisd-new and a Redis backend.
The Redis backend is mostly used for JSON logs.

I would like to use the penpal feature to optimise antispam filtering, so if I understand correctly the SMTP should hold the master Redis DB and PSYNC new penpals to MX's Redis slave DBs, is that correct?
Is there a way to sync penpals but not sync JSON logs? What would be the best way to setup the penpal feature in my situation?

Any help appreciated,
Thanks 

Patrick

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