HELP NEEDED: ftp, telnet and http problems (new RH 7.1 installation)

HELP NEEDED: ftp, telnet and http problems (new RH 7.1 installation)

Post by Jorge Padro » Thu, 23 Aug 2001 05:01:19



I just installed RH Linux 7.1, firewall settings = none, activated ftp
and telnet under /etc/xinted.d/telnet and /etc/xinted.d/wu-ftpd files
using the "disable = no" setting and then restarted xinted (service
xinetd restart)--everything went well.

My machine is part of a 2-computer home LAN, one machine runs Windows 98
and this one runs RH Linux 7.1 -- they are connected to each other and
to the Internet through a 4-port Linksys Cable/DSL switch router, using
an Internet cable connection. My Cable/DSL router has an internal IP
address of 192.168.1.1 (no DHCP); my Linux machine IP is 192.168.1.2 and
my Win98 is 192.168.1.3--I use my ISP's DNS servers for name resolution.
My Linksys router accepts connections to ports 21, 23 and 80 for
external incoming Internet connection (telnet, ftp and http ports) and
it forwards them to the internal IP 192.168.1.2, my Linux machine. All
other ports are blocked on the Linksys router. This setup worked 100%
well when my machine was previously running Win2000.

When I ftp or telnet my self (i.e. telnet 192.168.1.2 or ftp
192.168.1.2) from my own RH Linux machine, everything works well. When I
use Netscape Navigator on my own Linux machine to access my own Apache
web server (i.e. http://192.168.1.2/), I get the default index.html, no
problem ther either.

However, here's what happens when I try to connect from a remote
computer through the Internet (assume that my router WAN Internet IP
address is x.x.x.x):

1) ftp x.x.x.x will not give me the ftp logon prompt for at least 40
seconds. When it does, I can login using my Linux home logon account.
However, once I successfully logon to the ftp server, if I enter the
"ls" command to list my remote files, it will report a message such as
"Entering Passive Mode (192,168,1,2,84,2)" for about 1-2 minutes, then
the ftp server connection will die with the message "connect: Connection
timed out".

2) telnet x.x.x.x will take about 1-2 minutes to display the logon
prompt, then it will work well.

3) http://x.x.x.x/ will simply not work -- it will [unsuccessfully] try
to contact the host x.x.x.x for 1-2 minutes, then the web browser will
time out.

After reading about possible reverse dns lookup problems, I added a 2nd
line to my /etc/hosts file...

         192.168.1.2            machinename.domain.com  machinename

My original /etc/hosts file only had one line...

         127.0.0.1                machinename.domain.com  machinename
localhost.localdomain localhost

...so my /etc/hosts file now looks like this...

         127.0.0.1            machinename.domain.com  machinename
localhost.localdomain localhost
         192.168.1.2        machinename.domain.com  machinename

However, even with the new /etc/hosts file, I still have the same ftp,
telnet and http problems.

I'm at a loss here guys, what do I need to do to accomplish the simple
goal of allowing normal Intenet connections to my Linux machine using
telnet, ftp and http?

BTW, I've read a lot through USENET posts, but there were tons of
conflicting solutions to similar problems.

Thank you in advance,

J. Padron

 
 
 

HELP NEEDED: ftp, telnet and http problems (new RH 7.1 installation)

Post by Joshua Baker-LePai » Thu, 23 Aug 2001 05:45:11



> My Linksys router accepts connections to ports 21, 23 and 80 for
> external incoming Internet connection (telnet, ftp and http ports) and
> it forwards them to the internal IP 192.168.1.2, my Linux machine. All
> other ports are blocked on the Linksys router. This setup worked 100%
> well when my machine was previously running Win2000.
> 1) ftp x.x.x.x will not give me the ftp logon prompt for at least 40
> seconds. When it does, I can login using my Linux home logon account.
> However, once I successfully logon to the ftp server, if I enter the
> "ls" command to list my remote files, it will report a message such as
> "Entering Passive Mode (192,168,1,2,84,2)" for about 1-2 minutes, then
> the ftp server connection will die with the message "connect: Connection
> timed out".

Regular mode ftp uses two ports -- one for control, and one for data.
The data port isn't getting through.

Quote:> 2) telnet x.x.x.x will take about 1-2 minutes to display the logon
> prompt, then it will work well.
> I'm at a loss here guys, what do I need to do to accomplish the simple
> goal of allowing normal Intenet connections to my Linux machine using
> telnet, ftp and http?

You *do* realize, don't you, that your current setup offers you *no*
protection from having your username and password sniffed and the
attacker gaining access to your Linux box.

Turn off telnet and ftp.  Close those ports.  Activate ssh (it should
already be), and use it for remote communication *and* data transfer
(via scp or sftp).

As for the timeouts -- do DNS lookups work well from the Linux box?
I'm guessing not...

--
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University

 
 
 

1. RH 7.1 - telnet, FTP

My apologies in advance for the people who have answered these
questions 100x over... but my searching skills are failing to find the
answers that work (also, I have another problem - mentioned in a
previous post).

Telnet:  SSH works, and I have enabled telnet by turning off the
disable in Telnet (under xinetd.d).  I've restarted xinetd (even
restarted the system for that matter).  When I run netstat -a, it
shows the system is listening to port 23.  There is a file in
/usr/sbin called in.telnetd (I'm assuming this is the telnet program).
I've checked the logs, and there are NO entries when I attempt to
telnet.  (SSH attempts are logged fine).

FTP:  FTPing seems to work - BUT, it is incredibly slow logging in (30
seconds or so).  There is an entry in the hosts file, so I don't think
it's trying to do a reverse lookup via dns (the order is hosts, dns).

hosts.allow:  Please forgive me for this stupid question... but I am
not 100% sure of the format in this file.  (I checked the man page,
but I just wanted to be sure).  I've setup the files as follows:

  host.deny
    ALL : ALL

  hosts.allow
    ALL : 192.168.0.

  Does this seem reasonable if I am blocking all connections, except
those originated by the 192.168.0. range??

This new xinetd is making me feel like a "newbie" all over again (and
I thought I had a grasp on linux with RH6.1!)  

Thank in advance for any help!

KC

2. please critique this lilo.conf

3. RH 7.1: Applixware 4.4.2 needs older ldd need some help

4. Editor for LATeX?

5. Locked out of RH Box; no telnet, FTP, http

6. ADSL with PPP over ethernet

7. Problems with telnet, ipchains, RH 7.1

8. Home network suggestions sought

9. add new scsi drive to proliant 3000 RH 7.1 - help

10. Cannot ftp into RH 7.1 system--help?

11. RH 7.1 Installation Problem - fail at "Calibrating Delay Loop"

12. RH 7.1 Installation Problem

13. rh 7.1 - bogus http traffic