How to use ftp?

[Arctomachine]

I have always on vpn with block connections.

And with that computer in same network is unable to connect to ftp server running on phone.
But ping works

Is there special config to allow incoming ftp connections?

[ignoramous]

No special requirement that I can think of.

You can check Configure -> Logs -> DNS and Configure -> Logs -> Network to see if you spot any errors in the footer of the bottomsheet that comes up when you tap on entires listed in it. Use the search bar to filter for entries specific to the FTP domain / IP you're trying to hit.

You can also look for relevant Info / Warning / Error logs in About -> App Logs (use the search bar as a filtering mechanism, if there are too many logs; the logs are also saveable / exportable / shareable to other files / folders and also over email). The default log level is "Error", which you can switch from the pop-up when prompted... do remember to switch the log level before you hit your FTP server. This About -> App Logs log level will switch back to "Error" after ~3h to conserve battery.