Repadmin.exe helps system administrators diagnose Active Directory replication problems between domain controllers running Microsoft Windows operating systems.
For more about repadmin.exe
If you want view replication status and general health status, using command “/replsummary”.
This command will show you the percentage of replication attempts (Largest Delta/ Fails/Total/Error).
If you want view replication partner and status, using command “/showrepl”.
This command displays the GUID of each object that was replicated and it’s result.
Only to see the fail;
repadmin /showrepl /errorsonly
For other commands
If you don’t want to use commands, try this “Active Directory Replication Status Tool” 🙂
Have a nice day!