Finding Collisions With Cifs '8.3' Names - Acopia Adaptive Resource Switch Cli Maintenance Manual

Finding Collisions with CIFS '8.3' Names

CLI Maintenance Guide
Volumes that support CIFS have an additional naming-collision obstacle, caused by
back-end servers keeping an extra name for some files and directories. Windows once
ran on file systems (such as FAT12 and FAT16) that supported only short filenames,
sometimes called 8.3 names. An 8.3 name uses the following format:
base-name[.ext]
where
• base-name is 1-8 characters,
• . is optional, and
• ext is 1-3 characters.
Newer Windows servers run NTFS, which supports file and directory names of any
length. Other file systems that support CIFS also support names of any length. For
backwards compatibility, these modern file systems continue to support an alternate
8.3 name for any file or directory that does not fit the above pattern. The alternate
name is sometimes called a filer-generated name (FGN) since it is created by the filer.
The longer name is called the primary name. Modern-day Windows clients see the
primary name while older Windows applications see only the alternate name, the 8.3
FGN. Modern applications can use either name to access the file or directory, though
they do not see the alternate name by default.
Alternate names create another opportunity for naming collisions. If a primary name
matches the pattern for an 8.3 FGN, it collides with any matching alternate name on
another share. For example, consider a file on share A with a primary name of
"MYFILE~1" and a different file on share B named "myFileForYouToRead." If the
latter file has an alternate name of "MYFILE~1," it collides with the file on share A.
Troubleshooting Managed Volumes
Finding Collisions with CIFS '8.3' Names
8-57