Veja:
ProFTPD - Falha ao recuperar a listagem de diretórios ao usar o TLS
pode ser um problema com as regras relacionadas de um firewall entre você e o servidor.
Recentemente, migrei um servidor centOS 5 para 7. Mas desde então, a conexão com o FTP através do FileZilla não funciona, a menos que eu coloque o FileZilla no FTP Plain Connection.
O TLS não funciona ao obter a lista de pastas O login funciona bem. Mas isso acaba depois disso.
2016-04-10 11:29:59 3348 1 Status: Resolving address of something.com
2016-04-10 11:29:59 3348 1 Status: Connecting to x.x.x.x:21...
2016-04-10 11:29:59 3348 1 Status: Connection established, waiting for welcome message...
2016-04-10 11:29:59 3348 1 Response: 220 ProFTPD 1.3.5b Server ready.
2016-04-10 11:29:59 3348 1 Command: AUTH TLS
2016-04-10 11:29:59 3348 1 Response: 234 AUTH TLS successful
2016-04-10 11:29:59 3348 1 Status: Initializing TLS...
2016-04-10 11:29:59 3348 1 Status: Verifying certificate...
2016-04-10 11:29:59 3348 1 Status: TLS connection established.
2016-04-10 11:29:59 3348 1 Command: USER xxxxx
2016-04-10 11:29:59 3348 1 Response: 331 Password required for xxxxx
2016-04-10 11:29:59 3348 1 Command: PASS ***********
2016-04-10 11:29:59 3348 1 Response: 230 User xxxxx logged in
2016-04-10 11:29:59 3348 1 Command: OPTS UTF8 ON
2016-04-10 11:29:59 3348 1 Response: 200 UTF8 set to on
2016-04-10 11:29:59 3348 1 Command: PBSZ 0
2016-04-10 11:29:59 3348 1 Response: 200 PBSZ 0 successful
2016-04-10 11:29:59 3348 1 Command: PROT P
2016-04-10 11:29:59 3348 1 Response: 200 Protection set to Private
2016-04-10 11:29:59 3348 1 Status: Logged in
2016-04-10 11:29:59 3348 1 Status: Retrieving directory listing...
2016-04-10 11:29:59 3348 1 Command: PWD
2016-04-10 11:29:59 3348 1 Response: 257 "/" is the current directory
2016-04-10 11:29:59 3348 1 Command: TYPE I
2016-04-10 11:29:59 3348 1 Response: 200 Type set to I
2016-04-10 11:29:59 3348 1 Command: PASV
2016-04-10 11:29:59 3348 1 Response: 227 Entering Passive Mode (x,x,x,x,137,183).
2016-04-10 11:29:59 3348 1 Command: LIST
2016-04-10 11:30:19 3348 1 Error: Connection timed out after 20 seconds of inactivity
2016-04-10 11:30:19 3348 1 Error: Failed to retrieve directory listing
2016-04-10 11:31:41 3348 1 Status: Disconnected from server
A única coisa que consegui encontrar até agora é adicionar isso ao proftpd.conf
<IfModule mod_facts.c>
FactsAdvertise off
</IfModule>
Isso altera o comando para LIST em vez de MLSD. No entanto, ainda se expira sem motivo. Alguém tem alguma ideia?
EDIT: sem TLS a conexão funciona bem
2016-04-10 11:21:28 8704 1 Status: Resolving address of something.com
2016-04-10 11:21:28 8704 1 Status: Connecting to x.x.x.x:21...
2016-04-10 11:21:28 8704 1 Status: Connection established, waiting for welcome message...
2016-04-10 11:21:28 8704 1 Response: 220 ProFTPD 1.3.5b Server ready.
2016-04-10 11:21:28 8704 1 Command: USER xxxxx
2016-04-10 11:21:28 8704 1 Response: 331 Password required for xxxxx
2016-04-10 11:21:28 8704 1 Command: PASS ***********
2016-04-10 11:21:28 8704 1 Response: 230 User xxxxxlogged in
2016-04-10 11:21:28 8704 1 Command: SYST
2016-04-10 11:21:28 8704 1 Response: 215 UNIX Type: L8
2016-04-10 11:21:28 8704 1 Command: FEAT
2016-04-10 11:21:28 8704 1 Response: 211-Features:
2016-04-10 11:21:28 8704 1 Response: LANG en-US*
2016-04-10 11:21:28 8704 1 Response: EPRT
2016-04-10 11:21:28 8704 1 Response: EPSV
2016-04-10 11:21:28 8704 1 Response: MDTM
2016-04-10 11:21:28 8704 1 Response: SSCN
2016-04-10 11:21:28 8704 1 Response: SIZE
2016-04-10 11:21:28 8704 1 Response: PROT
2016-04-10 11:21:28 8704 1 Response: CCC
2016-04-10 11:21:28 8704 1 Response: PBSZ
2016-04-10 11:21:28 8704 1 Response: AUTH TLS
2016-04-10 11:21:28 8704 1 Response: REST STREAM
2016-04-10 11:21:28 8704 1 Response: UTF8
2016-04-10 11:21:28 8704 1 Response: 211 End
2016-04-10 11:21:28 8704 1 Command: OPTS UTF8 ON
2016-04-10 11:21:28 8704 1 Response: 200 UTF8 set to on
2016-04-10 11:21:28 8704 1 Status: Logged in
2016-04-10 11:21:28 8704 1 Status: Retrieving directory listing...
2016-04-10 11:21:28 8704 1 Command: PWD
2016-04-10 11:21:28 8704 1 Response: 257 "/" is the current directory
2016-04-10 11:21:28 8704 1 Command: TYPE I
2016-04-10 11:21:28 8704 1 Response: 200 Type set to I
2016-04-10 11:21:28 8704 1 Command: PASV
2016-04-10 11:21:29 8704 1 Response: 227 Entering Passive Mode (x,x,x,x,139,173).
2016-04-10 11:21:29 8704 1 Command: LIST
2016-04-10 11:21:29 8704 1 Response: 150 Opening BINARY mode data connection for file list
2016-04-10 11:21:29 8704 1 Response: 226 Transfer complete
2016-04-10 11:21:29 8704 1 Status: Directory listing of "/" successful
Veja:
ProFTPD - Falha ao recuperar a listagem de diretórios ao usar o TLS
pode ser um problema com as regras relacionadas de um firewall entre você e o servidor.