FTP Failed to retrieve directory listing

I am using ISPConfig 3.1.13 on Ubuntu 18.04 x64. I have configured two clients and fora each client, I have created 2 sites like site.domain1.com & domain1.com for client1 & so on. I have also created FTP accounts for each sites with domain root access.
Whenever I try to upload some files using FileZilla, I get the error as 'Failed to retrieve directory listing' after a long waiting of 'Retrieving directory listing of "/web/customization/css". This happens every time even if I reboot the server.
The server is hosted in Digital Ocean and there is no firewall behind the server network. Also, I have not enabled any firewall in the ISPC too.
In the monitoring section, no errors or warnings displayed except 1 or more components needs an update (Ubuntu update)
In the log, I found only these type of logs.
Nov 25 08:27:31 domain.com pure-ftpd: ([email protected]) [INFO] New connection from 157.49.141.123
Nov 25 08:27:31 domain.com pure-ftpd: ([email protected]) [INFO] domain_admin_ftp is now logged in

My Iptable rules show like this.
iptables -S (ipv4)
-P INPUT ACCEPT
-P FORWARD ACCEPT
-P OUTPUT ACCEPT

I have even tried by enabling passive ports range to 30000 50000 in pure-ftpd.conf (Uncommented). But still same problem. Is this because the server uses private IP and public IP for networking?
Please help me to resolve this problem.

 

Have you well restarted pure-ftpd-mysql service after changing its settings (passive ports range) ?

 

Yes, I have restarted entire server itself. But problem not solved.

 

Which one does pure-ftp use?
But the symptom you describe is common, and previously has been solved by setting passive port range and opening those ports in firewall.

 

Actually I have not configured the IP address in the pure-ftpd config files. I just entered both private and public IP addresses in the IP address section of the ISP config. I am not using any extra firewalls and in ispc, it is saying no firewalls found. So, i assume there is no firewall. The connection worka if I reboot the server for 1 or two connection attempts and then it starts to show retrieving directory listing message.

 

What kind of connection do you start in Filezilla? Plain FTP or SFTP? And what have you set up in Pure-FTPD?

 

Tried default connection (Explicit TLS) as well as plain ftp. If I use SSH of root user, it works fine.

 

I had faced same problem with my previous control panel centos web panel as well. For that reason i switched to ispc

 

I have checked it now from my office PC and did not get the problem. I will again check with my laptop and post the result. Thank you.

 

Only time when pure-ftp set up with ISPConfig caused problems was when new version of Filezilla had different defaults. It did not work until I figured out what settings it had changed and configured the settings properly.

 

Im still falling over this in 2022. Long live ISPConfig. lol
I had the same issue where Filezilla would auth fine but failed to load DIR listing. I tried WinSCP and at first it did the same until i disabled encryption. It seems pureftp was not enabled for encryption as im using port 21 for standard ftp instead of sftp. It confused me for a while as what is the requirement for the cert if its not going to use encryption. I guess there is a setting in pureftp to solve this.