The volume TTL and file TTL are not necessarily the same. as long as file TTL is smaller than volume TTL, it'll be fine. volume TTL is used when assigning file id, e.g. http://.../dir/assign?ttl=3h file TTL is used when uploading
2. when growing volumes, additional preferred "rack" and "dataNode" paraemters are also provided. Previously only "dataCenter" paraemter is provided.