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-   -   Can't reach my linux box at home using SSH (https://www.linuxquestions.org/questions/linux-networking-3/cant-reach-my-linux-box-at-home-using-ssh-4175436273/)

onyxbird 11-08-2012 10:28 AM

Can't reach my linux box at home using SSH
 
I have a slackware box version 13.0.0.0.0 at home which I cannot connect to anymore I used to be able to do this remotely from anywhere using my internet IP address, but now SSH just dies. However, on my local network it runs fine, I'm mostly connecting using secure shell on various windows machines (XP, 7) & Mac OSX 10.6 using the terminal. My ISP is frontier fios they didn't block port 22 before, but just encase I tried changing ports and still it drops unless I try https port (443) it thinks about it a bit then just hangs.... Any ideas anyone?

thanks in advance,

teckk 11-08-2012 10:46 AM

Quote:

However, on my local network it runs fine
Firewall in the way? Configure it.
Do you have a router in between your box and the internet that is doing NAT? Forward the port to the box.
Do you have a dynamic IP and the IP has changed?
Is sshd running on the Slack box? ps ax | grep sshd

What changed from the time you could until now?

manyrootsofallevil 11-08-2012 12:05 PM

Quote:

Originally Posted by teckk (Post 4825096)
Firewall in the way? Configure it.
Do you have a router in between your box and the internet that is doing NAT? Forward the port to the box.
Do you have a dynamic IP and the IP has changed?
Is sshd running on the Slack box? ps ax | grep sshd

What changed from the time you could until now?

I suspect that your problem is IP address has changed. Mine is supposed to be dynamic, but I've had the same ip for the past year and half.

Is there anything in the sshd logs (from your remote attempts, of course ;)) ?

onyxbird 11-09-2012 03:28 AM

Quote:

Originally Posted by teckk (Post 4825096)
Firewall in the way? Configure it.
Do you have a router in between your box and the internet that is doing NAT? Forward the port to the box.
Do you have a dynamic IP and the IP has changed?
Is sshd running on the Slack box? ps ax | grep sshd

What changed from the time you could until now?

Yes, I do have a router in between the slack box & the internet. I do have the port forwarded (22) to the ip address of the slackbox on the router. I have also tried several other custom ports also such as forwarding port 36665 -> 22 just to see if my ISP was blocking port 22, but that didn't work. I have checked the internet address of the router, and it is the correct one I'm using, and I have checked to make sure that the dynamic ip address of the slackbox is correct to and it is... From when it used to work until now nothing has changed, and I have changed nothing. Lastly yes the sshd daemon is running I checked it with ps -A & I can also ssh to my slackbox when I'm in my own LAN of course..... remote access not working....

onyxbird 11-09-2012 03:31 AM

Quote:

Originally Posted by manyrootsofallevil (Post 4825157)
I suspect that your problem is IP address has changed. Mine is supposed to be dynamic, but I've had the same ip for the past year and half.

Is there anything in the sshd logs (from your remote attempts, of course ;)) ?

Checked the ip addresses they are the same they have not changed, and my router configuration is still correctly pointed to the slack box. I haven't tried looking at the ssh logs I will check that out when I get home in the mornin after werk.

onyxbird 11-12-2012 12:43 AM

Still no use any other ideas?

catkin 11-12-2012 01:18 AM

You could use a packet tracing software such as tcpdump on your Slackware box to see to see if the packets are reaching it. If so, the router's OK and the problem is with the Slackware box. If not, the problem is with the router EDIT: or the packets are not reaching your router.

lleb 11-12-2012 07:20 PM

you could also run nmap -p22 <WAN_IP> to see if port 22 is open.

the output will look something like this:

Code:

$ nmap -p22 sisconsulting.biz

Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2012-11-12 20:18 EST
Interesting ports on rrcs-71-43-246-158.se.biz.rr.com (71.43.246.158):
PORT    STATE SERVICE
22/tcp open  ssh

Nmap finished: 1 IP address (1 host up) scanned in 0.163 seconds

It will either state open, or filtered. If filtered, then your ISP is blocking port 22.


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