Latest LQ Deal: Latest LQ Deals
Go Back > Forums > Linux Forums > Linux - Software
User Name
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.


  Search this Thread
Old 11-06-2006, 11:17 PM   #1
LQ Newbie
Registered: Nov 2006
Posts: 3

Rep: Reputation: 0
Problem with Putty and SSH

I am a new user of Putty and SSH, having never connected to a server this way before.

There are TWO remote servers I need to connect to.

I can get Putty to connect to Server A with no problem.

With Server B however, it times out. The strange thing is that my friend is able to connect to the same Server B without any problem.

So, the fact that I can connect to Server A suggests that my own PC is not blocking Putty from making connections, and the fact that my friend can connect to Server B suggests that it is set up correctly to accept connections on port 22.

What could be blocking my connection to Sever B?

Old 11-07-2006, 04:50 AM   #2
Senior Member
Registered: Mar 2006
Posts: 1,896

Rep: Reputation: 61
I understand you are getting no response back from server B rather than a refusal? I am not that familiar with firewalls on MS machines, but your symptom would make the firewall a leading contender I would think. Can you successfully ping server B? Or traceroute?

If you have a *nix box available you might see if you can connect from it, and if not use a packet sniffer to see what is going on. Or maybe there are packet sniffers you can use on MS?
Old 11-08-2006, 12:39 AM   #3
LQ Newbie
Registered: Nov 2006
Posts: 3

Original Poster
Rep: Reputation: 0
Problem partially solved

Thanks for replying.

We seem to have partially solved the problem by having APF disabled on the remote server.

According to our hosting company: "APF is a graphical dynamic proactive software that uses iptables, which is a Linux firewall software. It actively detects attacks on your server and tries to neutralize them."

I say "partially solved" because APF is still off, and we are told it should be on! So we now have to sort out how to have APF back on but not blocking my own IP address.
Old 11-08-2006, 08:04 AM   #4
Senior Member
Registered: Mar 2006
Posts: 1,896

Rep: Reputation: 61
APF apparently stands for Advanced Protection Firewall assuming my link is what you have running. I would think it would be quite configurable to get around whatever problem you are having w/o turning it off completely -- assuming you can figure out what is causing the problem. I did notice that it can be configured to use a dshield block list. I wonder if you are on that list. That would be a distinct possibility if you have a dynamically assigned IP address (where a previous user of the IP address used it maliciously, or was compromised). I believe you can check to see if your IP address is on that list at You can also check it at , where on arrival your address will be in their "IP Lookup" search box.

Last edited by blackhole54; 11-08-2006 at 08:05 AM.
Old 11-08-2006, 11:57 AM   #5
Registered: Mar 2004
Posts: 36

Rep: Reputation: 15
You will need to remove your IP from the following file.


Then add your IP to this file.


Then restart APF. That will ensure that your IP is safe from being blocked.
Old 11-09-2006, 07:25 PM   #6
LQ Newbie
Registered: Nov 2006
Posts: 3

Original Poster
Rep: Reputation: 0

Thanks everyone for your help. Much appreciated. I'm sure we'll get this problem solved now.
Old 11-18-2006, 09:32 AM   #7
Senior Member
Registered: Oct 2004
Location: Houston, TX (usa)
Distribution: MEPIS, Debian, Knoppix,
Posts: 4,727
Blog Entries: 15

Rep: Reputation: 234Reputation: 234Reputation: 234
The following kluge may offer a tmp solution:

PuTTY to A, then (inside PuTTY) ssh from A to B. This assumes that B is not blocking A.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Looking for some guidance: Putty problem or ssh config? starcutter Linux - Networking 9 08-13-2006 12:05 AM
SSH TUNNEL PROBLEM(putty to OpenSSH) Le Hara Linux - Security 3 03-26-2006 10:34 PM
Problem with remote terminal (ssh and PuTTY) guardian653 *BSD 11 02-09-2005 06:16 AM
Putty / SSH Problem on Mandrake 10.0 jalperin Linux - Newbie 1 09-02-2004 12:25 PM
SSH using putty rkemp Linux - Networking 3 03-06-2004 05:04 PM > Forums > Linux Forums > Linux - Software

All times are GMT -5. The time now is 03:51 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration