sftpMode

Specifies whether the Transfer Family server requires or ignores a PPv2 header containing the client's source IP address on incoming SFTP connections. If you don't specify a value, the default is NONE

• NONE: the server reads and ignores any PPv2 header on incoming SFTP connections. This is the default value. Use this value when your SFTP server is not behind an NLB, or when you do not need to preserve the client's source IP address through an NLB.

• PROXY_PROTOCOL_V2_ENFORCED: the server requires a valid PPv2 header on every incoming SFTP connection. When a valid header is present, the server applies it and uses the source IP address from the header. If a connection arrives without a PPv2 header, the server refuses the connection and logs an error to Amazon CloudWatch Logs indicating that the expected PPv2 header was missing. Use this value when your SFTP server is behind an NLB with PPv2 enabled on the target group.With PROXY_PROTOCOL_V2_ENFORCED you must restrict the server's VPC endpoint security group to allow inbound traffic only via the trusted NLB. For more information, see Working with Network Load Balancers.