ANSWER:-
thank you :)
Setting Up A Ftp:-
First of all, find out if your IP (Internet Protocol) is
static (not changing) or dynamic (changes every time you log on). To make it
static, just go to a place like http://www.myftp.org/ to register for a static
ip address. get your IP. This can be done by doing this:
Going to Start -> Run -> winipcfg
After doing so, you'll need to download an FTP server client. Serv-U FTPor Bullitproof v2.15
First, you'll have to set up your ftp. For this guide,use
step-by-step instructions for G6. First, you'll have to go into 'Setup ->
General'. From here, type in your port (default is 21). recommend something
unique, or something a bit larger (ex: 3069). The below options are then choose-able:
-Launch with windows
-Activate FTP Server on Start-up
-Put into tray on startup
-Allow multiple instances
-Show "Loading..." status at startup
-Scan drive(s) at startup
-Confirm exit
You can do what you want with these, as they are pretty self
explanatory. The scan drive feature is nice, as is the 2nd and the last option.
From here, click the 'options' text on the left column.
To protect your server, you should check 'login check' and
'password check', 'Show relative path , and any other options you feel you'll
need. After doing so, click the 'advanced' text in the left column. You should
then leave the buffer size on the and then allow the type of ftp you want.
Uploading and downloading is usually good, but it's up to
you if you want to allow uploads and/or downloads. For the server priority,
that will determine how much conventional memory will be used and how much
'effort' will go into making your server run smoothly.
Anti-hammering is also good, as it prevents people from
slowing down your speed. From here, click 'Log Options' from the left column.
If you would like to see and record every single command and clutter up your
screen, leave the defaults.
But, if you would like to see what is going on with the
lowest possible space taken, click 'Screen' in the top column. You should then
check off 'Log successful logins', and all of the options in the client
directry, except 'Log directory changes'. After doing so, click 'Ok' in the
bottom left corner.
You will then have to go into 'Setup -> User Accounts' .From
here, you should click on the right most column, and right click. Choose 'Add',
and choose the username(s) you would like people to have access to.
After giving a name ,you will have to give them a set
password in the bottom column. For the 'Home IP' directory, (if you registered
with a static server, check 'All IP Homes). If your IP is static by default,
choose your IP from the list. You will then have to right click in the very
center column, and choose 'Add'.
From here, you will have to set the directory you want the
people to have access to. After choosing the directory,weI suggest you choose
the options 'Read', 'List', and 'Subdirs', unless of course you know what
you're doing . After doing so, make an 'upload' folder in the directory, and
choose to 'add' this folder seperately to the center column. Choose 'write',
'append', 'make', 'list', and 'subdirs'. This will allow them to upload only to
specific folders.
Now click on 'Miscellaneous' from the left column. Choose
'enable account', your time-out (how long it takes for people to remain idle
before you automatically kick them off), the maximum number of users for this
name, the maximum number of connections allowed simultaneously for one ip
address, show relative path, and any other things at the bottom you'd like to
have. Now click 'Ok'.
From this main menu, click the little boxing glove icon in
the top corner, and right click and unchoose the hit-o-meter for both uploads
and downloads (with this you can monitor IP activity). Now click the lightning
bolt, and your server is now up and running.
Listing The Contents
Of A Ftp:-
Listing the
content of a FTP is very simple.You will need FTP Content Maker, which can be
downloaded from here:
1. Put in
the IP of the server. Do not put "ftp://" or a "/" because
it will not work if you do so.
2. Put in
the port. If the port is the default number, 21, you do not have to enter it.
3. Put in
the username and password in the appropriate fields. If the login is anonymous,
you do not have to enter it.
4. If you
want to list a specific directory of the FTP, place it in the directory field.
Otherwise, do not enter anything in the directory field.
5. Click
"Take the List!"
6. After the
list has been taken, click the UBB output tab, and copy and paste to wherever
you want it.
If FTP Content Maker is not working, it is
probably because the server does not utilize Serv-U Software.
If you get
this error message:
StatusCode =
550
LastResponse
was : 'Unable to open local file test-ftp'
Error = 550
(Unable to open local file test-ftp)
Error =
Unable to open local file test-ftp = 550
Close and
restart FTP Content Maker, then try again.
Active FTP vs.
Passive FTP, a Definitive Explanation:-
Introduction:-
One of the
most commonly seen questions when dealing with firewalls and other Internet connectivity
issues is the difference between active and passive FTP and how best to support
either or both of them. Hopefully the following text will help to clear up some
of the confusion over how to support FTP in a firewalled environment.
This may not
be the definitive explanation, as the title claims, however, I've heard enough
good feedback and seen this document linked in enough places to know that quite
a few people have found it to be useful. I am always looking for ways to
improve things though, and if you find something that is not quite clear or
needs more explanation, please let me know! Recent additions to this document
include the examples of both active and passive command line FTP sessions.
These session examples should help make things a bit clearer. They also provide
a nice picture into what goes on behind the scenes during an FTP session. Now,
on to the information...
The Basics:-
FTP is a TCP
based service exclusively. There is no UDP component to FTP. FTP is an unusual
service in that it utilizes two ports, a 'data' port and a 'command' port (also
known as the control port). Traditionally these are port 21 for the command
port and port 20 for the data port. The confusion begins however, when we find
that depending on the mode, the data port is not always on port 20.
Active FTP:-
In active
mode FTP the client connects from a random unprivileged port (N > 1024) to
the FTP server's command port, port 21. Then, the client starts listening to
port N+1 and sends the FTP command PORT N+1 to the FTP server. The server will
then connect back to the client's specified data port from its local data port,
which is port 20.
From the
server-side firewall's standpoint, to support active mode FTP the following
communication channels need to be opened:
FTP server's
port 21 from anywhere (Client initiates connection)
FTP server's
port 21 to ports > 1024 (Server responds to client's control port)
FTP server's
port 20 to ports > 1024 (Server initiates data connection to client's data
port)
FTP server's
port 20 from ports > 1024 (Client sends ACKs to server's data port)
In step 1, the client's command port contacts
the server's command port and sends the command PORT 1027.
In step 2 The server then sends an ACK back to the
client's command port.
In step
3 the server initiates a connection on its local data port to the data port
the client specified earlier.
In step 4 Finally, the client sends an ACK
back as shown.
The main
problem with active mode FTP actually falls on the client side. The FTP client
doesn't make the actual connection to the data port of the server--it simply
tells the server what port it is listening on and the server connects back to
the specified port on the client. From the client side firewall this appears to
be an outside system initiating a connection to an internal client--something
that is usually blocked.
Passive FTP:-
In order to
resolve the issue of the server initiating the connection to the client a
different method for FTP connections was developed. This was known as passive
mode, or PASV, after the command used by the client to tell the server it is in
passive mode.
In passive
mode FTP the client initiates both connections to the server, solving the
problem of firewalls filtering the incoming data port connection to the client
from the server. When opening an FTP connection, the client opens two random
unprivileged ports locally (N > 1024 and N+1). The first port contacts the
server on port 21, but instead of then issuing a PORT command and allowing the
server to connect back to its data port, the client will issue the PASV
command. The result of this is that the server then opens a random unprivileged
port (P > 1024) and sends the PORT P command back to the client. The client
then initiates the connection from port N+1 to port P on the server to transfer
data.
From the
server-side firewall's standpoint, to support passive mode FTP the following
communication channels need to be opened:
FTP server's
port 21 from anywhere (Client initiates connection)
FTP server's
port 21 to ports > 1024 (Server responds to client's control port)
FTP server's
ports > 1024 from anywhere (Client initiates data connection to random port
specified by server)
FTP server's
ports > 1024 to remote ports > 1024 (Server sends ACKs (and data) to
client's data port)
In step 1 the client contacts the server on
the command port and issues the PASV command.
In step 2 The server then replies with PORT
2024, telling the client which port it is listening to for the data connection.
In step 3 the client then initiates the data
connection from its data port to the specified server data port.
In step 4 Finally, the server sends back an
ACK to the client's data port.
While
passive mode FTP solves many of the problems from the client side, it opens up
a whole range of problems on the server side. The biggest issue is the need to
allow any remote connection to high numbered ports on the server. Fortunately,
many FTP daemons, including the popular WU-FTPD allow the administrator to
specify a range of ports which the FTP server will use. See Appendix 1 for more
information.
The second
issue involves supporting and troubleshooting clients which do (or do not)
support passive mode. As an example, the command line FTP utility provided with
Solaris does not support passive mode, necessitating a third-party FTP client,
such as ncftp.
With the
massive popularity of the World Wide Web, many people prefer to use their web
browser as an FTP client. Most browsers only support passive mode when
accessing ftp:// URLs. This can either be good or bad depending on what the
servers and firewalls are configured to support.
The following chart
should help admins remember how each FTP mode works:
Active FTP :
command :
client >1024 -> server 21
data :
client >1024 <- server 20
Passive FTP
:
command :
client >1024 -> server 21
data :
client >1024 -> server >1024
A quick
summary of the pros and cons of active vs. passive FTP is also in order:
Active FTP
is beneficial to the FTP server admin, but detrimental to the client side
admin. The FTP server attempts to make connections to random high ports on the
client, which would almost certainly be blocked by a firewall on the client
side. Passive FTP is beneficial to the client, but detrimental to the FTP
server admin. The client will make both connections to the server, but one of
them will be to a random high port, which would almost certainly be blocked by
a firewall on the server side.
Luckily,
there is somewhat of a compromise. Since admins running FTP servers will need
to make their servers accessible to the greatest number of clients, they will
almost certainly need to support passive FTP. The exposure of high level ports
on the server can be minimized by specifying a limited port range for the FTP
server to use. Thus, everything except for this range of ports can be
firewalled on the server side. While this doesn't eliminate all risk to the
server, it decreases it tremendously.
thank you :)
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