If you see messages reporting "dumping master file: tmp-abcdfghijk: open: Permission denied", particularly on a slave name server...
Check your named.conf and look at the zone file paths. If the zone files are in the top level named directory, the named service user may not have write permissions for them. Moving the zone files to the data subdirectory may solve the problem.
The named service user does not have permission to modify the top level directory for security purposes, therefore the sub directories are used.