In a multitenant container database (CDB), EM Express provides online redo log file information only in the root, not in the pluggable databases (PDBs).
To view online redo log file information:
The Redo Log Groups page appears. This page shows the attributes of the online redo log groups for your database.
When an online redo log group contains only one member, it is not multiplexed. Note the Status attribute for the online redo log groups. The online redo log group with status Current is the one currently being written to disk by the log writer.