In Solaris Release 2.4 and earlier, the /var/nis directory contained two files named hostname.dict and hostname.log. It also contained a subdirectory named /var/nis/hostname. Starting with Solaris Release 2.5, the two files were renamed trans.log and data.dict, and the subdirectory is named /var/nis/data.
In Solaris Release 2.5, the content of the files were also changed and they are not backward compatible with Solaris Release 2.4 or earlier. Thus, if you rename either the directories or the files to match the Solaris Release 2.4 patterns, the files will not work with either the Solaris Release 2.4 or the Solaris Release 2.5 or later versions of rpc.nisd. Therefore, you should not rename either the directories or the files.