I've been trying to find a way to share files seamlessly between Yosemite and a Quadra 800 running 8.1. In a perfect world, I'd enable file sharing on Yosemite and it would just work.
When the server is Snow Leopard (or better), the Quadra complains that the server is incompatible, which I take to mean "too new".
When the server is Leopard, the Quadra offers me only guest access, which already seems wrong, and then crashes trying to mount the only volume on offer. It's a fresh installation of Leopard, so I'm prrrrrretty sure I have not yet had the opportunity to screw up the configuration. In any case the crash doesn't seem like it could possibly be my fault.
When the server is netatalk atop Ubuntu within VirtualBox atop Yosemite, things seem to work acceptably. I like the fact that I've eliminated a machine but don't like the fact that I've added a virtual machine and have to indirect through an additional file system. I apparently don't dislike it enough to install netatalk directly on Yosemite.
I considered putting netatalk in a VPS but then realized AFP traffic, including passwords, is in the clear. Is an AppleShare client this old even capable of better? (The letters UAM are bouncing around in the back of my head.) If it can't do better, then I guess I could consider struggling with configuring a VPS which does site-to-site IPSec and run netatalk within a VLAN. Because that's easy to figure out. Not.
None of these solutions is quite as seamless as I would like, but of course the fact that I am able to get anything working at all already seems like a miracle. (You should have seen me cackle when I got the Quadra onto WiFi.)
Your linux netatalk solution is about the best I've come up with.
8.1 without additional 3rd party software, should only be doing appletalk, not AppleShare over TCP so isn't going to work with any modern system. OSX dropped AFP over appletalk in 10.4, and then in 10.6 dropped support for older versions of the AFP over TCP protocol as well so even OS9 clients can't connect.
netatalk on OSX will take some additional work, since netatalk relies on the host OS' appletalk implementation, which OSX doesn't have anymore (and even when it did, it was a weird interface that netatalk didn't adopt). There's some old AFP servers that predate unixes adopting appletalk support and include their own userspace appletalk implementation, like CAP. That could potentially be ported to a modern OSX and would take less work than netatalk appletalk on osx.
For this kind of sharing with System 7 emulated Macs in MESS, I use a shareware ($39) program called ShareWay IP Personal. It lets any 7.5.5 or later classic OS Mac fileshare seamlessly with a Leopard (10.5) server (I'm using my old G5 tower for this purpose). It "just works" in the classic Mac way, but if you'd rather not pay then the netatalk setup is probably your best bet.