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#Router2
/routing/bgp/connection
add name=toR1 remote.address=192.168.1.1 as=65532 local.role=ebgp

If you had in v6 config 
as=34 confederation=43 confederation-peers=1,2,3,4

Then confederation config to v7 translates as:
as=43/32

confederation-peers from v6 are not required in v7.

Property Reference

/routing/bgp/template

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