Should i use passive ftp mode

Create a personalised content profile. Measure ad performance. Select basic ads. Create a personalised ads profile. Select personalised ads. Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Bradley Mitchell. Updated on July 03, Tweet Share Email.

What is the difference between active and passive FTP? What is an FTP bounce attack? Additional information about constructing firewall rules can be found here. The following diagram outlines the flow of active FTP traffic, and what additional traffic needs to be allowed by the MX:. When configuring passive FTP, there is typically a field in your server side configuration that effectively tells the client "Use this IP address to connect for the data session.

When placed behind a stateful firewall like an MX Security Appliance, this will often be a private LAN address, and result in the client session attempting to connect to a nonexistent IP range to retrieve data.

When placed behind a firewall, this field must be changed to be the public IP that ports are being forwarded from, or the public IP in use for a NAT address on the firewall. Note: Microsoft IIS version 6 and earlier do not have a configurable option for server IP, which may cause issues when configuring passive FTP behind any stateful firewall.

This article provided an overview of the mechanisms used by active and passive FTP. For a more detailed discussion of passive and active FTP, please consult this documentation. The server responds with an ACK. The client sends an ACK to the server. The FTP session has now been established.

The client initiates a connection to the server on this ephemeral port. Two firewall rules are necessary for passive FTP to function properly: The firewall must allow connections on port Nowadays, it is typical that the client is behind a firewall e. For this reason the passive mode was introduced and is mostly used nowadays. It is a default for WinSCP too.

Using the passive mode is preferable because most of the complex configuration is done only once on the server side, by experienced administrator, rather than individually on a client side, by possibly inexperienced users. In the passive mode, the client uses the control connection to send a PASV command to the server and then receives a server IP address and server port number from the server, which the client then uses to open a data connection to the server IP address and server port number received.

Use Passive mode session settings to toggle between the active and the passive mode. With the passive mode, most of the configuration burden is on the server side. The server administrator should setup the server as described below. Typically, the FTP server software has a configuration option to setup a range of the ports, the server will use. It is common, that the FTP server is not configured properly and provides its internal IP address, that cannot be used from a client network.