[squid-users] FTP interrupted

[Garri Djavadyan]

On 2016-11-22 22:24, Garri Djavadyan wrote:
> On 2016-11-22 17:05, ludek_coufal wrote:
>> Hello,
>> Squid Cache ver. 3.3.8 on CentOs Linux 7.2.1511
>> 
>> FTP connection from local net over linux server CentOs firewall with
>> Squid proxy to internet FTP server is interrupted every 15 min (900
>> sec).
>> Large file upload is interrupted.
>> Direct connection without Squid proxy work OK.
> 
> Hi,
> 
> The issue may occur, if FTP client uses CONNECT method to connect to
> remote FTP servers. You can find details in the following thread:
> 
> http://www.squid-cache.org/mail-archive/squid-users/200609/0111.html

If your FTP client connects to Squid's http_port then it uses CONNECT 
method. To solve the problem try to use ftp_port and disable proxy 
settings on FTP client.
For example:

1. Configure ftp_port.
# diff etc/squid.conf.default etc/squid.conf
59a60
> ftp_port 21

2. Connect from FTP client, where:
${squid_ip} - Squid's IP address
${squid_ftp_port} - configured ftp_port
${username} - username on remote FTP server
${ftp_server} - remote FTP server name/IP
${password} - password for remote FTP server

$ ftp ${squid_ip} ${squid_ftp_port}
Connected to localhost.localdomain.
220 Service ready
Name (localhost:garry): ${username}@${ftp_server}
530 Must login first
530 Must login first
SSL not available
331 Please specify the password.
Password: ${password}
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp>


Garri