FTP reply code 120 tells the client that the server recognized the connection but is not currently ready to accept commands. The server is expected to become available within the time period indicated in the response message (typically expressed in minutes). This is a preliminary reply — the client should hold the connection open and wait for the server to send a 220 (Service Ready) response. This code is uncommon in modern FTP deployments but may appear when a server is starting up, performing maintenance, or waiting for a resource lock to be released.
The FTP daemon has accepted the TCP connection but is still loading its configuration, user database, or performing startup tasks. It sends 120 to indicate it will be ready shortly rather than refusing the connection outright.
The server is in a maintenance window — running integrity checks, updating user quotas, or performing disk operations. It accepts connections but cannot serve them until maintenance completes.
The server has reached its maximum concurrent connection limit and is queuing the new connection until a slot opens up. The delay indicated is an estimate of when a connection will become available.
The server has told you how long to wait. Keep the connection open and wait for the 220 response. Most FTP clients handle this automatically.
If the connection times out before the server becomes ready, disconnect and try again after the specified delay. The server should send 220 once it is ready.
ftp ftp.example.com
Verify that FTP ports 20 and 21 are open and reachable. If the server is behind a load balancer, other instances may be available immediately.
Scan Ports