I actually don't need to know this anymore because it ended up writing in a fairly timely manner. I also think I discovered what the issue is.
We have cifs.preserve_unix_security on on the particular filer I had issues with and I'm suspecting that this option requires user accounts to be able to be mapped from AD to whatever we are using for unix auth (in this case, ldap)...
I suspect that because of this, the user accounts that I noticed were failing, were ones that only had an AD account.
Can anyone confirm this behavior? I believe that my issue now lies with the wafl.default_unix_user being set to null instead of pcuser (or any other user).
I've set this option on a test filer, and my test account seems to work on... but to be honest I forgot to check it against the test filer before setting the option. I would like to clear this option now, but it seems that when I run the command to clear i, it comes back with it still set. Netapp documentation says this is how to clear this option. Any thoughts on why I can't clear it?
[1032]#[dmurphy@dfm01:~]$ sudo /usr/bin/rsh 2050b options wafl.default_unix_user ""
wafl.default_unix_user pcuser
[1033]#[dmurphy@dfm01:~]$ sudo /usr/bin/rsh 2050b options wafl | grep unix
wafl.default_security_style unix
wafl.default_unix_user pcuser