Issue Can't connect via FTP with some clients

[D4NY]

Hi everyone,
i've a strange situation on my Ovh Centos 6.8 Plesk 12.5 dedicated server. Suddenly (maybe after a freeze and phisical reboot) some users have problems connecting via FTP with clients like Filezilla of FileExplorer. They got a message like "A connection attempt failed because the connected party did not responded after a period of time". I've tried login with CuteFTP client and i log in after some seconds. If i try with Filezilla no way to login.

Before this issue with CuteFtp i login immediatly, exactly as on a second server with the same configuration. Log in is immediate and it works also with Filezilla and other clients.

What happened? Can someone help me?
Thank you

 

[Bitpalast]

1) Make sure that you are using "passive" FTP in your client.

2) Disable the software firewall. If disabling helps, add an FTP passive ports rule to it as described in (Plesk for Linux) Configuring Passive FTP Mode

 

[D4NY]

1) both clients are in passive mode. FileZilla not working (timeout). CuteFTP lasts lot of seconds and then log in and it's fast as normal.

2) no software firewall

 

[Bitpalast]

There is a possibility that the connection is proxied or that a virus on your system or an antivirus-software is interfering with it.

 

[AYamshanov]

Hi D4NY,

1) Could you provide detail logs from FileZilla?
2) Did you check OVH's firewall, client computer's firewall and server's firewall?

 

[Timo002]

Same issue here. Filezilla is not working on both Windows and Mac. Transmit on Mac has no issues at all.

Below the detail logs from FileZilla

Status:      Resolving address of ftp.domain.com
Status:      Connecting to x.x.x.x:21...
Status:      Connection established, waiting for welcome message...
Status:      Initializing TLS...
Status:      Verifying certificate...
Status:      TLS connection established.
Status:      Logged in
Status:      Retrieving directory listing of "/httpdocs"...
Command:    CWD /httpdocs
Response: 250 CWD command successful
Command:    PWD
Response: 257 "/httpdocs" is the current directory
Command:    TYPE I
Response: 200 Type set to I
Command:    PASV
Response: 227 Entering Passive Mode (x,x,x,x,156,184).
Command:    MLSD
Error:        Connection timed out after 20 seconds of inactivity
Error:        Failed to retrieve directory listing

 

[MarkM]

Are we sure the passive ports are open correctly?

(Plesk for Linux) Configuring Passive FTP Mode

 

[AYamshanov]

Response: 227 Entering Passive Mode (x,x,x,x,156,184).

In documentation, we recommend using 49152-65535 port range. Your FTP server asked FTP client use 40120/tcp port for passive connection but connection timed out.

Check what exactly port range do you use for passive FTP connection and allow it in firewalls (system's firewall; cloud's firewall if the system works in a cloud environment).

...or maybe some wrong with a firewall on a client side and the firewall blocks the outgoing connection.
Anyway, all this look like a network issue.