Reasons Why the NMC Cannot Connect to FTP

Issue:
Unable to connect or log in to the Network Management Card (NMC) using FTP. The connection may fail or return an error such as “421 Service Not Available, Closing Control Connection.”

Product Line:

Network Management Card Generations:

• NMC1
• NMC2
• NMC3

All Serial Numbers

Resolution:

The following are reasons why the NMC may be unable to connect to FTP:

SECTION 1: Active FTP Session Limit
The NMC accepts only one active FTP connection at a time. If another FTP session is active or a previous session did not close properly, a new connection may be rejected with a 421 Service Not Available, Closing Control Connection error.

For more information about "421 Service Not Available, Closing Control Connection". please refer to FAQ FAQ000283567

SECTION 2: FTP Server Is Disabled
FTP must be enabled on the NMC before a connection can be established. Note : FTP is disabled by default on all NMC3 and on NMC2 with FW 6.8 onwards.

Navigate to: Configuration > Network > FTP Server. Verify that the FTP server is enabled. After enabling the FTP Protocol Reboot the NMC. Navigate to: Control > Network > Reset/Reboot > Reboot Management Interface.

Activating FTP via CLI: Type in the syntax ftp -S enable. After enabling it reboot the NMC by typing in the syntax reboot

SECTION 3: Incorrect Credentials or Permissions
Verify that the correct username and password are being used and that the account has sufficient permissions to access FTP.

SECTION 4: Network or Firewall Restrictions
Verify that the network and firewall configuration allows FTP communication with the NMC. Blocked FTP traffic or incorrect network settings can prevent a connection.

SECTION 5: NMC Restart or Firmware Update
FTP access may be temporarily unavailable while the NMC is restarting, including after a firmware update. Allow the NMC to complete its restart before attempting to connect again.

Should there be any other questions and/or concerns, feel free to reach out to us at 1-800-800-4272 or via chat with our technical support group at Schneider Electric Customer Technical Support

Released for: Schneider Electric Netherlands