You can enable auditing through iManager.
In iManager, use one of the following methods to select a server in the tree where you are logged in:
In the Server field, type the NetIQ eDirectory distinguished server name for the server you want to manage, then press the Tab key or click somewhere on the page outside of the Server field to enter your selection. For example:
afpserver.novell
Click the Search icon to open the eDirectory Object Selector. Browse or search the list to locate the server you want to manage, then click the server name.
Click the Object History icon to select a server you have recently managed.
Wait for iManager to retrieve information about that server and display the appropriate information to the task page you are in.
Select the General tab and scroll down to Version and Logging.
Select the Auditing option. This checks the authentication process, and any changes that occur to the configuration parameters of the AFP server are logged in /var/log/audit/audit.log file.
Click OK to save and apply the changes.