Aliases are file names that are references or pointers to system-generated file names. However, aliases are user-friendly names. Aliases are similar to symbolic links in UNIX or Linux computers. You can create aliases to simplify Oracle ASM file name administration. You can create aliases with the mkalias ASMCMD command or a SQL ALTER DISKGROUP command.
An alias has at a minimum the disk group name as part of its complete path. You can create aliases at the disk group level or in any system-generated or user-created subdirectory. The following are examples of aliases:
+data/ctl1.f +data/orcl/ctl1.f +data/mydir/ctl1.f
If you run the ASMCMD ls (list directory) with the -l flag, each alias is listed with the system-generated file to which the alias refers.
ctl1.f => +data/orcl/CONTROLFILE/Current.256.541956473
For more information about aliases, refer to "Alias Oracle ASM File Name Forms".