I have been known to do this from time to time. On occasion, I have been required to move the online redo logs from one disk volume to another. Not wanting to schedule downtime for this action, I have devised the following strategy for doing this online:
Ensure your redo log group is INACTIVE by querying V$LOG. If ACTIVE, switch the log (ALTER SYSTEM SWITCH LOGFILE) and wait until the status is INACTIVE.
Next, drop the online redo log (with the ALTER DATABASE DROP LOGFILE GROUP x) command.
With the group removed, add the group anew in the new location (ALTER DATABASE ADD LOGFILE command.
Continue the above process until all logfile groups are moved to their new disk volume(s).
This was first published in August 2007