LoGFiles are not organized as the other datafiles.
They are not written with blocks but like a byte-stream.
Another different is that orcale supports morroring for logfiles,
probably due to this feature it is not possible to increase the size?
They way to increase the size is as written.
* add new bigger log-groups
* switch logfile to the new groups
* delete/drop the old groups
You cannot resize online redolog file.. i repeat
you CANNOT resize online redolog file..
but if you still want to.. there is a trick to do that...
1. create new larger redolog file <- make 2 or 3 files
2. switch current onle redo log file to the u havae created one
3. drop the 'old' online redo log file