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Old 03-07-2013, 09:27 AM   #1
shemeza
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can't access a remote server via ssh


hi,
i'm trying to send my public key(id_rsa.pub) to a remote server(172.18.3.255) without success. i used the below command
ssh-copy-id -i ~/.ssh/id_rsa.pub root@172.18.3.255

and the output was this:
ssh: connect to host 172.18.3.255 port 22: Connection timed out.

can anybody help me out?

thnx
 
Old 03-07-2013, 09:29 AM   #2
shivaa
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Ping it and check if it's alive & reachable:
Code:
~$ ping 172.18.3.255
 
Old 03-07-2013, 09:33 AM   #3
dinakumar12
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If its pinging do telnet 172.18.3.255 22
 
Old 03-07-2013, 09:35 AM   #4
druuna
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Also check to see if the port ssh listens on is actually 22:
Code:
nmap 172.18.3.255
(or if you have root access to 172.18.3.255):
Code:
netstat -pln | grep "sshd"
 
Old 03-07-2013, 11:07 AM   #5
lleb
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Quote:
Originally Posted by shemeza View Post
and the output was this:
ssh: connect to host 172.18.3.255 port 22: Connection timed out.
The computer is telling you that SSH is either not running, or it is not running on port 22. That or at the very least port 22 is blocked between you and the remote computer.

nmap is your friend for seeing if port 22 is open:

Code:
nmap -p22 <IP_of_Target_here>
That is the first thing you need to run. after that you will need to look into the ssh.conf of the remote system to see if its port has been changed, then if not you need to make sure it is running.
 
Old 03-08-2013, 03:51 AM   #6
shemeza
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i run the command "nmap -PN22 172.18.19.183" and the output was

Nmap scan report for 172.18.19.183
Host is up.
All 1000 scanned ports on 172.18.19.183 are filtered
Nmap done: 1 IP address (1 host up) scanned in 201.35 seconds

but still i'm not able to ping the 172.18.19.183
 
Old 03-08-2013, 04:05 AM   #7
Rumata
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Must be a firewall problem then.
 
Old 03-12-2013, 05:14 AM   #8
shemeza
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i manage to ping the server but i still have the same output when it's about to copy my id_rsa.pub to the server, "connection time out"
 
Old 03-12-2013, 05:35 AM   #9
jschiwal
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What do you mean by remote server. The address 172.18.19.183 is a private address. Is the server on your LAN?

If the server isn't on your local LAN, you need to go through the destination's firewall via its Internet IP address, which needs to forward port 22 to the server.
If the server has an interface connected directly to the internet, then you need it's Internet IP address.
 
Old 03-12-2013, 06:37 AM   #10
rahul.sed
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check the iptables rules
 
Old 03-12-2013, 08:43 AM   #11
lleb
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Quote:
Originally Posted by shemeza View Post
i run the command "nmap -PN22 172.18.19.183" and the output was

Nmap scan report for 172.18.19.183
Host is up.
All 1000 scanned ports on 172.18.19.183 are filtered

Nmap done: 1 IP address (1 host up) scanned in 201.35 seconds

but still i'm not able to ping the 172.18.19.183
Im not sure what the confusion is shemeza? The output of nmap flat out told you that port 22 is blocked. You either have to configure the firewall, or get whom ever is in charge of that system to grant you permission to ssh in. You will ALWAYS continue to have the same error msg. until you resolve this issue.

It can be caused by one of two things, mainly that is:

1. firewall issues (either hardware or software to include but not limited to iptables)
2. ssh is not running on that server therefore port 22 is not open.
 
Old 03-18-2013, 04:51 AM   #12
shemeza
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i managed to connect, now it's ok
 
  


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