As Bloomberg News put it today in a story about Alpha, some mines must die for others to live. And some companies will also die. CONSOL Energy Inc. (NYSE: CNX) is the largest coal producer by market cap, but its survival plan is based on becoming a natural gas producer.So far that has been only a partial success because natural gas prices are so low.nd some companies will also die. CONSOL Energy Inc. (NYSE: CNX) is the largest coal producer by market cap, but its survival plan is based on becoming a natural gas producer. So far that has been only a partial success because natural gas prices are so low.
From the server-side firewall's standpoint, to support passive mode FTP the following communication channels need to be opened: 1  FTP server's port 21 from anywhere (Client initiates connection)  FTP server's port 21 to ports > 1023 (Server responds to client's control port)
After the correct FTP username and password is entered through the FTP client software, the FTP server software opens port 21 by default, which is sometimes called the command or control port. 1  Then, the client makes another connection to the server over port 20 so that the actual file transfers can take place.