DobiMiner: Error: Unicode Is Enabled, But Some DobiMiner Proxies Will Receive Non UTF-8 File Names ISO-8859-1

During the Validate Configuration you will receive an error message indicating that the encoding cannot represent all possible Unicode characters (ISO-8859-1).

Error: Unicode mode is enabled on the VNX, but some DobiMigrate proxies will receive file names in an encoding that cannot represent all possible Unicode characters (ISO-8859-1). This may lead to incorrect filenames during the migration.

A VNX system can operate in one of two modes: ASCII or Unicode.  ASCII is the default, but in practice most systems are going to be set to Unicode. 
When operating in Unicode mode, file and directory names on the file system are stored in Unicode formats.
By default, all clients use ISO-8859-1, but this is something that may have been changed by the system administrators.

Since the character encoding in the NFSv3 protocol is unspecified, and the VNX filesystems store filenames in Unicode, DobiMiner tries to ensure that a Unicode encoding (UTF-8) is used when it talks to VNX systems over NFS.
DobiMiner checks this by asking the VNX system which encoding would be used for the DobiMiner NFS proxy IP addresses.
If that comes back with anything other than UTF-8, then the I18N precheck will fail.

We can control the encoding that is used when sending/receiving file names over NFSv3. This is done using the 'xlt.cfg' file.
It contains rules to choose the encoding based on the client IP address.

The Fix option [button at the right of the error message] you see when setting up a migration will automatically update the `xlt.cfg` file with a rule specific to the DobiMiner NFS proxy IP address, telling the VNX to use UTF-8 for those addresses.

Basically it means that if you don't "Fix" this, DobiMigrate proxies will receive filenames in ISO-8859-1 encoding instead UTF-8.
 
You can proceed with the migration setup but in case DobiMigrate generates errors regarding specific characters (like German, French characters), you still need to enable this afterwards.

Having ISO-8859-1 encoded filenames does not mean they will have non-UTF-8-compatible characters but they might have.
If they do not have non-compatible characters then there is no issue skipping the "Fix" option (and most implementations will not be affected as they will not be using those characters).
However, if they have any incompatible characters and you select not to "Fix" the issue during pre-check then DobiMigrate will throw an exception and the 'xlt.cfg' will need to be modified for the migration of that specific client (i.e. VNX VDM).