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ittechlabFlag for Canada

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vsftpd

I did install vsftpd on redhat linux 6. I need help with the following.  I have disabled selinux and flushed the iptables. So there is no security measure here as per my knowledge.

1. what is passive and active?  How do i know what is my current status. is it passive or active setup?
2. How do i change the log file. instead of xferlog, I need vsftpd.log should be generated.
3. when I tried to ftp from windows, I get the following message and it hung.

C:\Users\Owner\Desktop>ftp 192.168.3.127
Connected to 192.168.3.127.
220 (vsFTPd 2.2.2)
User (192.168.3.127:(none)): mano
331 Please specify the password.
Password:
230 Login successful.
ftp>
ftp> ls
200 PORT command successful. Consider using PASV.
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Dave Baldwin
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The built-in Windows FTP is pretty crippled.  You should consider using an FTP client like Filezilla or CoreFTP.  They are much more capable.

PASV mode is initiated by the client.  FTP uses many 'ephemeral' ports above 1024 while it is in operation.  However, firewalls sometimes don't allow that.  So instead of the server using the ephemeral ports, the client does and that's called PASV mode.
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when we install vsftpd first time in linux, what is the default mode? is it passive or active?

how do i confirm?
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Dave Baldwin
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does vsftpd support both modes ?
Yes, most FTP servers support both modes and probably All of them on Linux.  It's only the Windows FTP that doesn't that I know of.
what is the main diff in active and passive? which one is better
Neither is better.  Active mode does not work thru some firewalls and that is when you must use passive.  Other than the way they use ports, they are the same.  Remember, the Client selects the mode, not the server.
do you know how to change the log file in vsftpd?

How do i change the log file. instead of xferlog, I need vsftpd.log should be generated.
Here's the 'man' page for vsftpd.conf: http://vsftpd.beasts.org/vsftpd_conf.html  If you set 'dual_log_enable' to YES you will get both formats.
I did add the following parameter.  but still don't see any logs in vsftpd.log file.
dual_log_enable'=YES

[root@localhost ~]# tailf /var/log/vsftpd.log
[root@localhost ~]# cat /etc/vsftpd/vsftpd.conf | grep -v ^#
anonymous_enable=YES
local_enable=YES
write_enable=YES
local_umask=022
anon_upload_enable=YES
dual_log_enable=YES
dirmessage_enable=YES
xferlog_enable=NO
connect_from_port_20=YES
xferlog_std_format=YES
listen=YES

pam_service_name=vsftpd
userlist_enable=YES
tcp_wrappers=YES


pasv_enable=YES
pasv_min_port=6000
pasv_max_port=6010
Did you restart vsftpd or reboot the server?  You probably won't see anything in the vsftpd.log file until something has been transferred.  I doubt that vsftpd will make copies of what is already in the other log file.
I did reboot the system. Now its logging.
Good.  It's doing what you want it to now?
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shinuster

Active Mode:

Client initiate command channel from Client Port (eg:x) to Server Port (20/21)
Client will sends Port to server and server acknowledges on command channel.
Server will open data channel to establish data connection.
Client will send Ack to Server

Passive Mode:

Client will opens both command and data channel prior to the data transfer.
Server send Ack on data channel.

For the easiness and flexibility...I recommend Passive mode to be enabled as if in case server can't open data channel due to firewall settings, client will open both command and data channel in Passive mode.
Well windows FTP does not support passive mode,and since it expects to oprn random port on clients system it needs to be specifically allowed via local firewall
I tried from another linux machine and its same. I don't see port 20
because other linux machine has proper ftp client that uses passive mode by default, so no chance to see port 20 unless you switch off passive mode.
i did see its using passive
but i don't see 20
passive mode does not receive connections from FTP server, port 20 or any other.
I suggest to stop iptables completely if you not using it and also check the intermittent firewall between servers and clients because default mode of FTP is always active in case you are unable to access and forced to enter in passive mode then their must be something intermittent which is blocking this access.

TY/SA
Windows client ftp.exe does not support passive mode at all
from windows filezilla or winscp can be used to check this