Tnsping, "Used parameter files" is empty

Question

I am using Ruby API oci8 to connect to a remote Oracle DB, got ORA 12514.

My operating system is linux, the weird thing is when I do:

tnsping <hostname:port>

I get:

TNS Ping Utility for Linux: Version 10.2.0.2.0 Production on 22-JUL-2017 14:46:28

Copyright (c) 1997, 2005 Oracle Corporation.  All rights reserved.

Used parameter files:

Used HOSTNAME adapter to resolve the alias
Attempting to contact (DESCRIPTION = (CONNECTDATA = (SERVICE_NAME= my-orasvr.db)) (ADDRESS= (PROTOCOL =TCP)(HOST = 10.15.222.44)(PORT = 1521))) 
OK (0 msec)

The "Used parameter files" is empty, not sure whether it does matter.

Don't have any clue, any help is appreciate~!!