How can I block access to public server IP for OpenSSH in Debian?

Posted by VanDerSpar on Server Fault See other posts from Server Fault or by VanDerSpar
Published on 2012-10-11T07:46:09Z Indexed on 2012/10/11 9:40 UTC
Read the original article Hit count: 128

Filed under:

linux

|

ssh

|

firewall

I got a Debian server with a public and a private IP in a DMZ. I need to be able to connect to it through SSH on our private side, and then block all access to the public address. Both /etc/hosts.deny and sshd_config seems to only let one block incoming IP addresses. What I really want is to disable SSH connections for the public IP. I've been trying iptables, but I haven't had luck with that neither.

Any help is appreciated.

© Server Fault or respective owner

Related posts about linux

apt-get install and update fail

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I've got a problem with apt-get update and apt-get install ... commands . every time update or installing fails and errors are : Get:1 http://dl.google.com stable Release.gpg [198B] Ign http://dl.google.com/linux/chrome/deb/ stable/main Translation-en_US Get:2 http://dl… >>> More
kernel module compiling error

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
sh@ubuntu:/home/ccpp/helloworld$ make gcc-4.6 -O2 -DMODULE -D_KERNEL_ -W -Wall -Wstrict-prototypes -Wmissing-prototypes -isystem /lib/modules/`uname -r`/build/include -c -o hello-1.o hello-1.c hello-1.c:4:0: warning: "MODULE" redefined [enabled by default] <command-line>:0:0: note: this is… >>> More
Build-Essentials installation failing

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I am having trouble accessing the several critical header files that show to be a part of the build process. The "Ubuntu Software Center" shows "Build Essentials" as installed: Next I did the following two commands, which did not improve the problem: ~$ sudo apt-get install build-essential [sudo]… >>> More
Updating Debian kernel

as seen on Super User - Search for 'Super User'
I'm trying to update my Debian machine to 2.6.32-46 (which is the new stable). However, after doing apt-get update my apt-cache search linux-image shows me: linux-headers-2.6.32-5-486 - Header files for Linux 2.6.32-5-486 linux-headers-2.6.32-5-686-bigmem - Header files for Linux 2.6.32-5-686-bigmem linux-headers-2… >>> More
Serial connection over a single USB cable (Windows to linux, or linux to linux)

as seen on Server Fault - Search for 'Server Fault'
I'm helping out with a project for an embedded device that only has USB and no serial. This device is running Linux. These days, when we need to connect to a serial port on a device we typically use a USB to serial adapter (on something like a phone system or a load balancing device, etc). I would… >>> More

Related posts about ssh

Problem with hadoop start-dfs.sh

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I installed and configured hadoop on my Ubuntu 14.04 server, virtualized inside of hyper-v, however I am getting an issue when i run start-dfs.sh root@sUbuntu01:/var/log# start-dfs.sh 14/06/04 15:27:08 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java… >>> More
SSH problems (ssh_exchange_identification: read: Connection reset by peer)

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I was running 11.10 and decided to do the full upgrade and come up to 12.04 after the update SSH (not SSHD) is now misbehaving when attempting to connect to other OpenSSH instances. I say OpenSSH as I am running a DropBear sshd on my router and I am able to connect to it. When attempting to connect… >>> More
SSH main process ended

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a running ubuntu server 10.04.1. When I tried to login to the server via ssh, I could not. Instead, I got connection refused error. I tried to ping the machine and I got reply! So, the clear reason is that SSH daemon is stopped. After reboot, I was able to login to my server via ssh. After… >>> More
SSH server not working (respawns until stopped)

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I have a running Ubuntu Server 10.04.1. When I tried to login to the server via ssh, I could not. Instead, I got connection refused error. I tried to ping the machine and I got reply! So, the clear reason is that SSH daemon is stopped. After reboot, I was able to login to my server via ssh. After… >>> More
Cannot SSH after resetting firewall on VPS

as seen on Server Fault - Search for 'Server Fault'
I'm having trouble trying to SSH to my Debian 5 VPS with blacknight. It was working fine until I did the following: Logged into 'Parallels Infrastructure Manager' - Container - Firewall - Set to 'Normal Firewall settings'. It told me there was an error with the IPTables and offered the option again… >>> More