Is it possible to only replicate indexes and not the mail data

[Marc Roos]

>> Is it possible to only replicate indexes and not the mail data? 
>> (Because the data is already on distributed storage)

> Does replication re-copy data that is already on the replication 
server? 
> I don't think it does.

Hmmm, maybe I do not understand fully. But if your emails are stored on
distributed storage. Then regardless if an email is received on srv1 or
srv2, it is stored on this distributed storage, and thus 'available' on 
both
servers.
However only on 1 server the index will be updated, the server that 
receives this email. Can't this get messy with how replication is 
described
on this page[1]. 
Only the index needs to be updated on the other server.

[1]
https://wiki.dovecot.org/Replication
"The replication is done by looking at Dovecot index files (not what 
exists in filesystem)"