Finding domain controllers replicating from a particular server

This will look at all ntds server connections in each site to find which servers (listed in the distinguishedname attribute) are replicating from a particular machine (in the fromServer attribute).

get-adobject -searchbase `
("CN=Sites," + (get-adforest).partitionscontainer.substring(14)) `
-ldapfilter "(objectclass=nTDSConnection)" `
-Properties distinguishedname,fromServer |select distinguishedname,fromServer |
where {$_.fromserver -match "servername"}