Changes were made in Mac OS X Lion to the library that manages the Apple Filing Protocol in many servers and NAS (network-attached storage) boxes. Unhappily for many customers, the new code breaks AFP file access and Time Machine backups on many third-party devices. Worse, customers continue to purchase these products without a warning from NAS makers to Lion users.
I was glad that La Cie this week released Lion updates to its NAS utilities. The titles include LaCie Desktop Manager, LaCie Intego, LaCie NAS OS (Dashboard Administrator), LaCie Safe Manager, LaCie Setup Assistant, LaCie Shortcut Button, LaCie Private-Public, and LaCie Professional NAS (Windows® Storage Server 2008/Windows Home Server).
To maintain compatibility with Mac OS X Lion, we highly recommend that you download the most recent versions of all your LaCie software. Doing so will help to avoid any potential problems when using your LaCie software utility
What happened is that the developers of NetATalk, NetAFP, came out with its Netatalk 2.2.0 code that it supplied to paying customers. It didn't update NAS makers who thought this was a free, open-source project.
So the situation is that some vendors have upgraded their software, others have released command-line code that may or may not fix the issue, and others are balking at paying a licensing fee.
The outrage is that some NAS vendors aren't revealing their level of support. It is hard to see much evidence of the Lion issue on the sales support pages for many NAS vendors. You have to dig deep into the support discussions, which would only happen if you knew of the problem.
Certainly, one will be wise to check out whether there's complete Lion compatibility on a NAS box you're preparing to purchase.