FTPS not working for Personal FTP Backup Repository

[Fritz MichaelG]

I am using a Personal FTP Repository for my Backups. The connection works fine if I don't use FTPS, however, whenever I try to activate FTPS, I just get this error message:

Error: FTP connection failed, please check your FTP settings.
Repository error: Transport error: unable to list directory: Curl error: Couldn't connect to server

I think this is because of a missing installed SSL certificate for the Apache Server or something? I am unable to use CURL with SSL encryption in general (i.e. when I try to open a remote address with https:// for instance, CURL is unable to connect as well, in one of my own applications). I am unsure what to do in order to fix this. I'd prefer to use FTPS instead of a completely unencrypted connection.

For the record, I checked the connection to the other FTP server via FTPS with FileZilla for instance, which works fine.

 

[abdi]

Check that your firewall (if you have any) is not blocking connections out of your server to that port. (Basically ensure that the FTPS port is open in your firewall.)

 

[Fritz MichaelG]

Check that your firewall (if you have any) is not blocking connections out of your server to that port. (Basically ensure that the FTPS port is open in your firewall.)

Connection on that port in general works (also the passive ports). The port for FTP and FTPS is simply the same. As I mentioned, the regular FTP connection works fine, only FTPS fails.

 

[abdi]

Connection on that port in general works (also the passive ports). The port for FTP and FTPS is simply the same. As I mentioned, the regular FTP connection works fine, only FTPS fails.

FTPS port is not always the same as FTP unless if you defined that...also since you can use filezilla minus any problems, then firewall is likely the issue here..

 

[Fritz MichaelG]

FTPS port is not always the same as FTP unless if you defined that

Well, FTPES is always the same port, i.e. with an explicit FTP connection over TLS, the connection port will always be the same as the regular FTP port, since there is no technical difference, only the connection method.

However, could it be that the Plesk Panel is always trying to make an FTPIS connection? i.e. implicit FTP over TLS? Because that fails on the target server even with FileZilla on my Laptop (for reasons I don't know yet). Implicit FTP over TLS requires an additional port. Or is the implicit mode just called FTPS? I am never sure on that. (And, hence, a hint to what Plesk actually uses.)


Regarding the firewall: it's a hosted root server, there is no additional local firewall, I should be able to use all connection on all ports as far as I know, but I'll ask the hoster none the less.