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dear all,
I need to reach a remote machine (my slack 10.2 at office) via a ssh
connection from home.

At home, I have a slack10.2 laptop, connected to the internet via ADSL.
If I boot the laptop in windows, the ssh client reaches without
problems the remote machine.

However, If I boot in linux, the ssh client does not reach the machine,
and returns a "connection time out".
The same if I try to connect to other machines, which the windows client
is anyway able to reach.

Therefore, the problem should be in the ssh configuration of my local
machine.
I have tried re-installing openssh, and the problem remains.
I have checked the dependencies of the openssh package via swaret, and
dependencies appear to be fine.

What could be the problem???

best regards

On Sat, 26 Nov 2005 10:04:50 +0000
Giorgio Corani <gcoraniREMOVETHIS@gmail.com> wrote:


>
> What could be the problem???
>
> best regards


In the folder .ssh there should be a file known_hosts. If there isn't maybe your ssh client does not have write to your directory. Another possiblity it your trying to use ssh as root and it is set not to allow you which is a common security feature.

hth
mAineAc

>
> In the folder .ssh there should be a file known_hosts. If there isn't
> maybe your ssh client does not have write to your directory.

Indeed, it was lacking.
I added the file via touch, but the problem remains the same


I also checked the permissions of .ssh:

drwx------ 2 giorgio users 48 2005-11-23 20:47 .ssh/

which should be correct.

Another
> possiblity it your trying to use ssh as root and it is set not to
> allow you which is a common security feature.

no, I am trying as normal user.

On 11/26/05 13:26, Giorgio Corani wrote:
>
>>
>> In the folder .ssh there should be a file known_hosts. If there isn't
>> maybe your ssh client does not have write to your directory.
>
>
> Indeed, it was lacking.
> I added the file via touch, but the problem remains the same
>
>
> I also checked the permissions of .ssh:
>
> drwx------ 2 giorgio users 48 2005-11-23 20:47 .ssh/
>
> which should be correct.

Did your installatione create the host key files?

If not try the following (as root):

# Create host keys if needed.
if [ ! -r /etc/ssh/ssh_host_key ]; then
/usr/bin/ssh-keygen -t rsa1 -f /etc/ssh/ssh_host_key -N ''
fi
if [ ! -f /etc/ssh/ssh_host_dsa_key ]; then
/usr/bin/ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key -N ''
fi
if [ ! -f /etc/ssh/ssh_host_rsa_key ]; then
/usr/bin/ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N ''
fi


Ciao
Giovanni
--
A computer is like an air conditioner,
it stops working when you open Windows.
Registered Linux user #337974 <http://counter.li.org/>

Giorgio Corani wrote:
> However, If I boot in linux, the ssh client does not reach the machine,
> and returns a "connection time out".
> The same if I try to connect to other machines, which the windows client
> is anyway able to reach.
>
> Therefore, the problem should be in the ssh configuration of my local
> machine.

not necessarily. there might be other things that prevent ssh from
connecting.

> I have tried re-installing openssh, and the problem remains.
> I have checked the dependencies of the openssh package via swaret, and
> dependencies appear to be fine.

that was most likely a futile exercise. unless the existing install was
corrupt, you don't solve config problems by reinstalling.

> What could be the problem???

there are a gazillion things that could be wrong. you should probably read
up a little on ssh configuration, so you can troubleshoot better: read the
man page and google a bit. first thing to try is if your linux box can
reach the hosts you're trying to connect to: try pinging them, for
example. then run ssh with one or more -v switches and see what that tells
you. (see man ssh for details.)

--
Joost Kremers joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

Giorgio Corani wrote:

> dear all,
> I need to reach a remote machine (my slack 10.2 at office) via a ssh
> connection from home.
>
> At home, I have a slack10.2 laptop, connected to the internet via ADSL.
> If I boot the laptop in windows, the ssh client reaches without
> problems the remote machine.
>
> However, If I boot in linux, the ssh client does not reach the
> machine, and returns a "connection time out".
> The same if I try to connect to other machines, which the windows
> client is anyway able to reach.
>
> Therefore, the problem should be in the ssh configuration of my local
> machine.
> I have tried re-installing openssh, and the problem remains.
> I have checked the dependencies of the openssh package via swaret, and
> dependencies appear to be fine.
>
> What could be the problem???
>
> best regards

This may seem kind of silly, but... is the daemon running?

ps -ef | fgrep ssh

should show something like

root 4801 1 0 Nov24 ? 00:00:00 /usr/sbin/sshd

If not, make sure that /etc/rc.d/rc.sshd is executable (chmod 755
/etc/rc.d/rc.sshd), and start it with

/etc/rc.d/rc.sshd start

then try your connection.

As suggested by others, you should be able to ping the server you're
trying to connect with -- unless the machine is configured to not reply
to ping (which is a good idea -- keeps the script kiddies out of your
pants). You should be able to traceroute to it, though if it doesn't
respond to ping traceroute will just stop at the last connection.
That'll at least tell you that you're getting to the outside world cleanly.

Perhaps I did some progress, though the connection isn't working yet.

a)The keys were already there; nevertheless, I generated them ex novo
(thanks Giovanni).
They should be definitely fine.

b) I can reach via both ping and traceroute the machines I am interested
in, besided reaching them via the ssh windows client

c)I guess the problem is here:

giorgio@lap-darkstar ~ $ ssh corani@[remote-host-name] -v
OpenSSH_4.2p1, OpenSSL 0.9.7g 11 Apr 2005
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Connecting to [remote-host-name] [1.0.0.0] port 22.
^^^^^^^
debug1: connect to address 1.0.0.0 port 22: Connection timed out
^^^^^^^
ssh: connect to host [remote-host-name] port 22: Connection timed out

so basically, it looks for host 1.0.0.0, although tracereoute or ping
can flawlessy reach the host.
I am connected via an ADSL router.

any further suggestions?

thanks

Giovanni <lsodgf0@home.net.it> wrote:
> # Create host keys if needed.
> if [ ! -r /etc/ssh/ssh_host_key ]; then
> /usr/bin/ssh-keygen -t rsa1 -f /etc/ssh/ssh_host_key -N ''
> fi
> if [ ! -f /etc/ssh/ssh_host_dsa_key ]; then
> /usr/bin/ssh-keygen -t dsa -f /etc/ssh/ssh_host_dsa_key -N ''
> fi
> if [ ! -f /etc/ssh/ssh_host_rsa_key ]; then
> /usr/bin/ssh-keygen -t rsa -f /etc/ssh/ssh_host_rsa_key -N ''
> fi

That part will already be done by the /etc/rc.d/rc.sshd script.

To the original poster: that script MUST exist and be executable on the
machine you're trying to reach. It generates the host keys and starts up the
sshd daemon, the one which will RECEIVE an incoming ssh connection attempt.
Further look at the permissions for the daemon in /etc/hosts.allow, it must
allow your laptop to connect TO the server. sshd has built-in tcp wrappers,
so when you got a non-blank hosts.deny you must enable "systems that MAY use
ssh to this machine" in the hosts.allow, like this:
sshd : 130.161. 145.94. .nl # SSH from within the university and the .nl domain allowed
Finally, also look at the server config in /etc/ssh/sshd_config, the defaults
may not be what you want.
For instance, by default "X11 forwarding" is disabled, so if you use ssh -X
(or -Y) it will not work:
#X11Forwarding no
(remove the # and change to "yes", the commented entries are the built-in
defaults of the daemon).
--
************************************************** ******************
** Eef Hartman, Delft University of Technology, dept. EWI/TW **
** e-mail: E.J.M.Hartman@math.tudelft.nl, fax: +31-15-278 7295 **
** snail-mail: P.O. Box 5031, 2600 GA Delft, The Netherlands **
************************************************** ******************

Thomas Ronayne wrote:
> This may seem kind of silly, but... is the daemon running?

you don't need an ssh daemon running if you want to use the ssh
client. sshd is used when you want to allow others to connect *to* your
box, not when you want to connect to a remote server *from* your box.

> trying to connect with -- unless the machine is configured to not reply
> to ping (which is a good idea -- keeps the script kiddies out of your
> pants).

i'm not sure if script kiddies use ping to see if there are doors to knock
on. they may just try and connect directly, without trying to ping first.

--
Joost Kremers joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

Giorgio Corani wrote:
> Perhaps I did some progress, though the connection isn't working yet.
>
> a)The keys were already there; nevertheless, I generated them ex novo
> (thanks Giovanni).
> They should be definitely fine.

i strongly suggest you do some reading on ssh and how it connects. you have
a problem, and the way you go about solving it is a typical "windows" way:
shooting in all directions, hoping that one shot will hit the target.

what i'm saying is, there is absolutely no point in generating new keys if
they are not the cause of your problem. and as is obvious from the rest of
your post, they aren't your problem.

when you have a problem, the right way to go about solving it is to find
out what exactly the problem is. anything else will lead to wasted time,
even if you do manage to accidentally solve it, because you will not have
learned *why* whatever you did turned out to be a solution.

> c)I guess the problem is here:
>
> giorgio@lap-darkstar ~ $ ssh corani@[remote-host-name] -v
> OpenSSH_4.2p1, OpenSSL 0.9.7g 11 Apr 2005
> debug1: Reading configuration data /etc/ssh/ssh_config
> debug1: Connecting to [remote-host-name] [1.0.0.0] port 22.
> ^^^^^^^
> debug1: connect to address 1.0.0.0 port 22: Connection timed out
> ^^^^^^^
> ssh: connect to host [remote-host-name] port 22: Connection timed out
>
> so basically, it looks for host 1.0.0.0, although tracereoute or ping
> can flawlessy reach the host.

a quick look through the ssh, ping and traceroute binaries suggests that
they do indeed use different methods for resolving host names. perhaps one
of them isn't working on your box. at the very least, this result does
suggest that something about your host name resolution isn't configured
properly.

i assume you can connect by ip address?

> I am connected via an ADSL router.
>
> any further suggestions?

perhaps increase the number of -v switches, like the man page says. though
i'm not sure that will give you any useful info.

--
Joost Kremers joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)