sshd : connection refused

alexklant · 08-11-2005, 07:26 AM

Hi there!

This is my first try to set up an remote login with ssh on ubuntu.
sshd is up and running, and my router is open and fowared on that ports.
The dyndns is working too.
But whenever i try to connect to my own machine via the routers ip
i get:

Code:

ssh: connect to host ***.homelinux.org port 22: Connection refused

same with an ftpd that i set up for testing.
This is what i tried:

Code:

Starting nmap V. 2.54BETA31 ( www.insecure.org/nmap/ )
Warning:  You are not root -- using TCP pingscan rather than ICMP
Interesting ports on ***.bredband.skanova.com (217.***.***.***):
(The 1548 ports scanned but not shown below are in state: filtered)
Port       State       Service
21/tcp     closed      ftp                     
22/tcp     open        ssh                     
23/tcp     closed      telnet                  
80/tcp     closed      http                    
88/tcp     closed      kerberos-sec            
2111/tcp   closed      kx

netstat shows thow:

Code:

Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:21              0.0.0.0:*               LISTEN     5882/inetd
tcp6       0      0 :::22                   :::*                    LISTEN     12027/sshd

i am trying to get kerberos to work too (this was the original project),
but i get an

Code:

kinit: krb5_get_init_creds: Incorrect net address

from there too, related to NAT-issue they said on the net.

I tried also an

Code:

 sudo iptables -A INPUT -p tcp --dport ssh -j ACCEPT

but nothing...

Someone help?

Regards, Alex

camorri · 08-11-2005, 08:48 AM

Have you edited your /etc/hosts.allow and hosts.deny files? You need to make sure they are set up so you can get in from ip addresses you want access from.

alexklant · 08-11-2005, 09:00 AM

i insterted

Code:

ALL: ALL

in the /etc/hosts.allow file.
Yet nothing changed.

carl.waldbieser · 08-13-2005, 01:06 PM

Are you running a firewall on the ssh server? Can you ssh to it from a machine on the local network?

alexklant · 08-14-2005, 07:46 AM

Not that i know of. Otherwise Ubuntu installs an firewall on default. I can connect to the server from its own via 192.168.0.2 .

Regards, Alex

carl.waldbieser · 08-14-2005, 11:45 AM

Quote:

Originally posted by alexklant
Not that i know of. Otherwise Ubuntu installs an firewall on default. I can connect to the server from its own via 192.168.0.2 .

Regards, Alex

OK, if you can ssh locally to the Ubuntu machine, that narrows down the list of possible problems. They could be:

+ Router is not correctly configured to forward to correct machine and/or port.
+ Connectivity does not exist between Ubuntu and router (test with ping).
+ Ubuntu is blocking port via netfilter. Test:

Code:

$ sudo iptables -nL

Should show the following for no firewall:

Code:

Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

+ sshd is not configured to accept traffic from the source you are trying to send from. You could test this by disabling sshd temporarily, and then run

Code:

$sudo nc -l -p 22

This will start a generic netcat process listening on port 22. If you are able to ssh to your computer, netcat will receive the data being sent and spit it out to the screen (it may look like random garbage, so you might want to redirect it to a file). Also try checking the logs (dmesg) to see if something went wrong.

If you are connecting from a GNU/Linux box, "ssh -v", "ssh -vv" and "ssh -vvv" can spit out more diagnostic info.

alexklant · 08-14-2005, 01:50 PM

Carl, thanks a lot.

I was trying to connect from my own pc via the dyndns adress. I was able to ssh to my university server,
and from there to my pc. It works perfectly.
But thanks for your help, it is always nice to see guys like you at work.

Regards, Alex

eckardman89 · 04-15-2009, 06:15 AM

Hi

I am having the exact some problem but cannot figure out what to do next. I am able to ssh from local address but get port 22 connection refused when i try remotely.... I have checked and there is no firewall and my router is set up to forward those ports. Any suggestions???

dasy2k1 · 04-18-2009, 06:54 PM

if you go to shields up and run a probe on your machine (all service ports) what does it show port 22 as?

eckardman89 · 04-19-2009, 08:26 AM

It shows that port 22 is open on my machine.

repo · 04-19-2009, 08:30 AM

Quote:

get port 22 connection refused when i try remotely

are you logging in as a user the system knows ?
root logins ar ot allowed

try

Code:

ssh -vv user@remote_IP

oxleyk · 04-19-2009, 03:37 PM

If you haven't done so already make sure your public IP corresponds with what dyndns has. You have to use something like ipcheck or ddclient to update the IP with dyndns.

Kent