To convert a directory to a qtree in UNIX, you rename the directory, create a qtree on the storage system, and move the directory's contents to the qtree.
client: mv /n/joel/vol1/dir1 /n/joel/vol1/olddir
system1: qtree create /n/joel/vol1/dir1
client: mv /n/joel/vol1/olddir/* /n/joel/vol1/dir1
client: rmdir /n/joel/vol1/olddir
Depending on how your UNIX client implements the mv command, file ownership and permissions might not be preserved. If this occurs, update file owners and permissions to their previous values.