Telnet and Ftp

Telnet and Ftp

[John J. Boyer]

Hello,
i'm wondering if I have to log in twice to my Web server if I first do ftp 
to upload some files and then do telnet to make some onsite changes 
without disturbing the copies on my local system.
I have a DSL connection? Can I safely leave telnet running for hours when 
i want to make occasional changes to the romote site?
Thanks.
John


-- 
Computers to Help People, Inc.
http://www.chpi.org
825 East Johnson; Madison, WI 53703

Re: Telnet and Ftp

[Rafael Skodlar,,,]

telnet and ftp are different animals and you cannot combine them into
one. But let's take care of the security first. Telnet and ftp are
terribly insecure outside little private networks. Since ssh or it's
cousin OpenSSH are free it makes no sense to use telnet on public
networks anymore. I use telnet only to test a port on remote server when
troubleshooting some services. It's good for connecting to mail server
on port 25 for example since you don't do anything with real passwords.

Use ssh in place of telnet and scp in place of ftp. That way your
communication is encrypted all the way. It is possible to setup
authentication so that you do not need to type the password each time
you connect to the remote machine. I leave ssh connection open from work
to my home system over T-1 and DSL all day long. I also use a utility
screen which allows me to switch between numerous virtual terminals all
under single ssh session.

On Sun, Aug 11, 2002 at 01:47:31PM -0500, John J. Boyer wrote:
> Hello,
> i'm wondering if I have to log in twice to my Web server if I first do ftp 
> to upload some files and then do telnet to make some onsite changes 
> without disturbing the copies on my local system.
> I have a DSL connection? Can I safely leave telnet running for hours when 
> i want to make occasional changes to the romote site?
> Thanks.
> John
> 
> 
> -- 
> Computers to Help People, Inc.
> http://www.chpi.org
> 825 East Johnson; Madison, WI 53703

-- 
Rafael
The Gap Between the Rich and the Poor is Constant.

Re: Telnet and Ftp

[Raul A. Gallegos]

Rafael Skodlar,,, said the following on Sun, Aug 11, 2002 at 12:33:20PM -0700:
> Use ssh in place of telnet and scp in place of ftp. That way your
> communication is encrypted all the way. It is possible to setup
> authentication so that you do not need to type the password each time
> you connect to the remote machine. I leave ssh connection open from work
> to my home system over T-1 and DSL all day long. I also use a utility
> screen which allows me to switch between numerous virtual terminals all
> under single ssh session.

Can you tell me what utility this is?  I'm interested.  Thanks.

Re: Telnet and Ftp

[John J. Boyer]

Raul,
Screen is a program that enables you to run multiple programs frrom a 
single terminal or vertual console. I use it all the time. it is very 
useful. To use it, just type "screen" and press enter at your Linux 
prompt. This will start screen off You will see a new prompt. You can 
now run any program. When you want to start another program from the 
same terminal without quitting the first one type control-a, c. This 
will give you a blank screen with a prompt. start your second program. 
When you want to switch back to the first, type control-a, 0. If you 
want to start still a third program, type control-a, c. This will create 
yet another blank screen with a prompt in which you can run a program. 
You can have up to ten screens on the same terminal.
I hpe this gives you the idea. There is documentation on the screen 
utility, but it takes you through all the options before explaining how 
to simply get started using it.
John
On Mon, 12 Aug 2002, Raul A. Gallegos 
wrote:

> Rafael Skodlar,,, said the following on Sun, Aug 11, 2002 at 12:33:20PM -0700:
> > Use ssh in place of telnet and scp in place of ftp. That way your
> > communication is encrypted all the way. It is possible to setup
> > authentication so that you do not need to type the password each time
> > you connect to the remote machine. I leave ssh connection open from work
> > to my home system over T-1 and DSL all day long. I also use a utility
> > screen which allows me to switch between numerous virtual terminals all
> > under single ssh session.
> 
> Can you tell me what utility this is?  I'm interested.  Thanks.
> 
> 
> 
> _______________________________________________
> Blinux-list mailing list
> Blinux-list@redhat.com
> https://listman.redhat.com/mailman/listinfo/blinux-list
> 

-- 
Computers to Help People, Inc.
http://www.chpi.org
825 East Johnson; Madison, WI 53703

Re: Telnet and Ftp

[Luke Davis]

Being someone who does the same as the writer of the below, I will note
the "sftp" program, as an alternative to scp.  It has a more interactive,
FTP-ish interface.

Luke
 On Sun, 11 Aug 2002, Rafael Skodlar,,, wrote:

> telnet and ftp are different animals and you cannot combine them into
> one. But let's take care of the security first. Telnet and ftp are
> terribly insecure outside little private networks. Since ssh or it's
> cousin OpenSSH are free it makes no sense to use telnet on public
> networks anymore. I use telnet only to test a port on remote server when
> troubleshooting some services. It's good for connecting to mail server
> on port 25 for example since you don't do anything with real passwords.
>
> Use ssh in place of telnet and scp in place of ftp. That way your
> communication is encrypted all the way. It is possible to setup
> authentication so that you do not need to type the password each time
> you connect to the remote machine. I leave ssh connection open from work
> to my home system over T-1 and DSL all day long. I also use a utility
> screen which allows me to switch between numerous virtual terminals all
> under single ssh session.
>
> On Sun, Aug 11, 2002 at 01:47:31PM -0500, John J. Boyer wrote:
> > Hello,
> > i'm wondering if I have to log in twice to my Web server if I first do ftp
> > to upload some files and then do telnet to make some onsite changes
> > without disturbing the copies on my local system.
> > I have a DSL connection? Can I safely leave telnet running for hours when
> > i want to make occasional changes to the romote site?
> > Thanks.
> > John
> >
> >
> > --
> > Computers to Help People, Inc.
> > http://www.chpi.org
> > 825 East Johnson; Madison, WI 53703
>
>

Re: Telnet and Ftp

[Darrell Shandrow]

Hi John,

Don't use telnet!  Use ssh instead.

Thanks.

----- Original Message -----
From: "John J. Boyer" <director@chpi.org>
To: <blinux-list@redhat.com>
Sent: Sunday, August 11, 2002 11:47 AM
Subject: Telnet and Ftp


> Hello,
> i'm wondering if I have to log in twice to my Web server if I first do ftp
> to upload some files and then do telnet to make some onsite changes
> without disturbing the copies on my local system.
> I have a DSL connection? Can I safely leave telnet running for hours when
> i want to make occasional changes to the romote site?
> Thanks.
> John
>
>
> --
> Computers to Help People, Inc.
> http://www.chpi.org
> 825 East Johnson; Madison, WI 53703
>
>
>
>
>
> _______________________________________________
> Blinux-list mailing list
> Blinux-list@redhat.com
> https://listman.redhat.com/mailman/listinfo/blinux-list

Re: Telnet and Ftp

[John]

The accounts don't have to have the same name for this to work. I can connect 
(as root) to other machines on my LAN:
[summer@numbat summer]$ ssh -l root gw
Last login: Sat Aug 17 14:27:26 2002 from numbat.computerdatasafe.com.au
[root@gw root]#

I actually have this set up as a function in ~/.bashrc:
[summer@numbat summer]$ grep -A4 root .bashrc
function root()
        {
                RH=$1
                shift
                [ -z "$RH" ] && RH=${HOSTNAME}
                ssh -t -l root $RH $@
                return $?
        }

so that I can access the machine:
[summer@numbat summer]$ root gw w
 12:08pm  up 42 days,  1:03, 10 users,  load average: 0.28, 0.11, 0.09
USER     TTY      FROM              LOGIN@   IDLE   JCPU   PCPU  WHAT
<snip>
valhalla pts/9    numbat.computerd Fri 4pm 43:34m  0.06s  0.06s  -bash
root     pts/10   numbat.computerd 12:08pm  1.00s  0.04s  0.04s  w
Connection to gw closed.
[summer@numbat summer]$ root gw
Last login: Sun Aug 18 12:08:47 2002 from numbat.computerdatasafe.com.au
[root@gw root]#

The root command without operands logs in as root on my own machine.


On Sunday 18 August 2002 00:21, Martin McCormick wrote:
> If the system you are connecting to via
> ssh is one where you also have an account with the same name, you
> can exchange public keys between the .ssh directory you have on
> each system and make it so you don't even have to use a password
> when jumping from one system to another.

-- 


Cheers
John.

Please, no off-list mail. You will fall foul of my spam treatment.
Join the "Linux Support by Small Businesses" list at 
http://mail.computerdatasafe.com.au/mailman/listinfo/lssb

Re: Telnet and Ftp

[Shaun Oliver]

*SNIP*
the only real difference between
using that and telnet is that you type ssh somewhere.org instead
of telnet somewhere.org.
Not quite true.
with ssh you need to issue the command in one of 2 ways.
You can either use, ssh user@some.where where user@some.where is your user
account on the remote machine, or use
ssh -luser some.where where the -l flag tells ssh that you want to login
as a specific user.
hth


-- 
Shaun Oliver


In a world without fences
          and walls who needs Windows and Gates?

EMAIL: shaun_oliver@optusnet.com.au
ICQ: 76958435

Re: Telnet and Ftp

[Luke Davis]

Also, if properly using the config file, you can have a system like:

something.somethingelse.test.edu

With a user name of:

testuser

Using the config file, you can have:

ssh tu

be a valid way of getting there, using host declarations.



On Sat, 17 Aug 2002, Martin McCormick wrote:

> 	Once you get ssh going, the only real difference between
> using that and telnet is that you type ssh somewhere.org instead
> of telnet somewhere.org.  If the system you are connecting to via
> ssh is one where you also have an account with the same name, you
> can exchange public keys between the .ssh directory you have on
> each system and make it so you don't even have to use a password
> when jumping from one system to another.  If you aren't careful
> and let somebody have your password in to one of the systems,
> they, of course, have access to all of them so you need to be
> very careful how and where you use this feature, but it is quite
> useful in some instances.
>
> 	You also should keep track of the security bulletins
> regarding ssh and sshd.  Occasionally, holes are discovered in
> ssh that either let the bad guys in or allow a bad guy or girl to
> send traffic to a system that prevents proper users from logging
> in.  Either way, you loose control of your system and any systems
> they are connected to.
>
> 	Remember that if you don't expect to log in to a given
> system but will only use that system to make connections to the
> big wide world, you don't need to run sshd on that box because
> sshd is the daemon that accepts connections from other places.
> It also is used when you use scp so you'll just have to decide
> whether or not you will need it.
>
> 	It is very good technology, the price is right, and the
> manual is good and useful.  Read it to learn how to generate and
> handle your keys safely.
>
> Martin McCormick WB5AGZ  Stillwater, OK
> OSU Center for Computing and Information Services Network Operations Group
>
>
>
> _______________________________________________
> Blinux-list mailing list
> Blinux-list@redhat.com
> https://listman.redhat.com/mailman/listinfo/blinux-list
>

Re: Telnet and Ftp

[Martin McCormick]

	Once you get ssh going, the only real difference between
using that and telnet is that you type ssh somewhere.org instead
of telnet somewhere.org.  If the system you are connecting to via
ssh is one where you also have an account with the same name, you
can exchange public keys between the .ssh directory you have on
each system and make it so you don't even have to use a password
when jumping from one system to another.  If you aren't careful
and let somebody have your password in to one of the systems,
they, of course, have access to all of them so you need to be
very careful how and where you use this feature, but it is quite
useful in some instances.

	You also should keep track of the security bulletins
regarding ssh and sshd.  Occasionally, holes are discovered in
ssh that either let the bad guys in or allow a bad guy or girl to
send traffic to a system that prevents proper users from logging
in.  Either way, you loose control of your system and any systems
they are connected to.

	Remember that if you don't expect to log in to a given
system but will only use that system to make connections to the
big wide world, you don't need to run sshd on that box because
sshd is the daemon that accepts connections from other places.
It also is used when you use scp so you'll just have to decide
whether or not you will need it.

	It is very good technology, the price is right, and the
manual is good and useful.  Read it to learn how to generate and
handle your keys safely.

Martin McCormick WB5AGZ  Stillwater, OK 
OSU Center for Computing and Information Services Network Operations Group