Is this still happening on latest ML and rc8?

I've not had any of these issues.

I am also seeing severe issues with AFP from a Mac running Mountain Lion (10.8.2).

 

The Finder will randomly tell me that the server has shut down (it hasn't), and I'll see an afpd crashdump in the syslog. Other times I just get the "server connection interrupted" window and nothing in the syslog.

 

I have set my drives to mount on boot with an Automator script in my login items, which helps Time Machine find the disk a bit better but it still drops out randomly, and large file copies almost always get interrupted.

 

I've also backed up and erased my flash drive and reinstalled unRAID from scratch. The problem persists.

 

This was working perfectly under Lion... though I was running an earlier beta/rc of UnRAID 5.0 back then.

AFP and Time Machine are unusable for me - Finder will crash almost every day, accessing shares seems to take forever, initial TM backup (~200GB) took about almost a week, incremental backups are virtually impossible (10MB takes 4 hours), disks will spin up every 15 minutes when there is any user share mounted in Finder.

 

I switched to SMB. I can now acess my shares almost instantly, they are mounted in Finder 24/7 and there is no disk spin-up problem. Sure I can't use TM, but seeing how it was unusable anyways it doesnt make any difference.

 

Netatalk/TM backups worked fine on Ubuntu 

I've switched to SMB for the time being. Compared to the AFP issues under Mountain Lion, this is rocksolid.

 

There's a convoluted way of using Time Machine over SMB which is detailed here: http://rajiv.sg/blog/2012/11/19/configuring-os-x-mountain-lion-time-machine-to-work-with-cifs-smb-share/ -- it's working well for me so far.

 

Restoring from Time Machine over SMB isn't great (warning: you can't do it from the OS X installer!) but if your machine does totally die and you need to restore from an SMB backup, there's this process: http://www.mageuzi.com/blog/?p=467 which will at least let you get your home directory back.

 

This definitely isn't an ideal setup but it's better than having no backups at all.

I hope this works for you. I tried using SMB for TM in the past and the sparcebundle would become corrupted every few months and requires restarting the backup fresh. The entire previous history is lost.

Yeah that does happen sometimes, though you can normally fix that by following this process: http://www.garth.org/archives/2011,08,27,169,fix-time-machine-sparsebundle-nas-based-backup-errors.html