#GOOGLE FTP SERVER CODE#

However, it times out and fails to connect when using the custom VPC network. The Cloud Function works as expected and connects to the FTP server when using the default VPC network. Return 'Successfully connected to FTP server', 200 Return 'Failed to connect to FTP server', 500 If not test_ftp_connection(server, username, password): If request_json and 'server' in request_json:Įlif request_args and 'server' in request_args: If request_json and 'password' in request_json:Įlif request_args and 'password' in request_args: If request_json and 'username' in request_json:Įlif request_args and 'username' in request_args: Request_json = request.get_json(silent=True)

#GOOGLE FTP SERVER CODE#

My Cloud Function can access the internet using the custom VPC network (e.g., by sending an HTTP request to ) and retrieve the static IP configured on the cloud-nat, but it fails to connect to the FTP server only when using the custom VPC network.īelow is the Cloud Function code I'm using to connect to the FTP server: import osĭef test_ftp_connection(server, username, password):įtp.login(user=username, passwd=password).I have verified that the custom VPC network is configured with a Cloud NAT gateway to allow instances (and the VPC Connector) to access the internet.I have copied the firewall rules from the default VPC network to the custom VPC network, ensuring that they allow the same traffic (including the rule for default-allow-internal with the custom subnet's IP range).I have set up a VPC Connector associated with the custom VPC network and configured the Cloud Function to use this VPC Connector.The Cloud Function successfully connects to the FTP server when using the default VPC network, but it fails to connect when using a custom VPC network, even though the settings are an exact replica of the default VPC network. My Cloud Function uses a VPC Connector to access resources in my VPC network. The only solution found for google cloud (for now): to hack the ftp client (in my case it's simple: ruby) forcing the sending of the real external network address in the ftp PORT command.I am trying to connect to an FTP server using a Google Cloud Function. I don't know if in the google environment is possible this kind of solution. The routing device in this example would then forward all traffic for this connection to and from the client address at 192.168.1.2:1930. The remote server would then attempt to connect to 17.254.0.26:1930. When the packet containing this PORT reaches the routing device, it should be rewritten like this, assuming the external address is 17.254.0.26: The device would then have to route the connection incoming from the remote FTP server back to the internal network address of the client. Devices can keep track of FTP data connections, and when a client on a private network uses 'PORT' with an internal network address, the device should dynamically rewrite the packet containing the PORT and IP address and change the address so that it refers to the external IP address of the routing device. The Solution: The solution depends from the network administrator of the client network to use high-quality network address translation software. The big problem is that when a client program is using network address translation to hide behind a routing device on an internal network, when using PORT the client tells a server on the external network to connect to an address on the client's internal network. Google Drive can do that, but it is hard to manage online sharing among different services like FTP does. I found the solution! Under google cloud network is not possible to establish an active ftp connection with an external ftp server. FTP, in most instances, is used to share and edit files. TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 There are no firewall rules in the local machine. The server accept only active mode connections (no passive). In the 'google firewall' I opened all ports from (ftp server address). In my opinion there are some problem in the NAT / port forwarding rules between local and public IP. I saw another post without any solutions about active mode connection from google cloud. it seems impossible to establish an active ftp connection with an external ftp server.

Running a Google Compute Instance with an internal interface mapped to a temporary public IP.

Google ftp server