Skip to main content

How To Install DenyHosts on Linux

About DenyHosts


DenyHosts is a security tool written in python that monitors server access logs to prevent brute force attacks on a linux server. The program works by banning IP addresses that exceed a certain number of failed login attempts. 

Step One—Install Deny Hosts


DenyHosts is very easy to install on Ubuntu
#  apt-get install denyhosts
On RHEL/Centos:
We need epel repo to install fail2ban on RHEL/Centos based machines.
So, download the rpm:-
and, then install
# yum install denyhosts
Once the program has finished downloading, denyhosts is installed and configured on your linux server. 


Step Two—Whitelist IP Addresses


After you install DenyHosts, make sure to whitelist your own IP address. Skipping this step will put you at risk of locking yourself out of your own machine. 

Open up the list of allowed hosts allowed on your server:
vim /etc/hosts.allow

Under the description, add in any IP addresses that cannot afford to be banned from the server; you can write each one on a separate line, using this format:
# sshd: 12.34.45.678

After making any changes, be sure to restart DenyHosts so that the new settings take effect on your linux server:
# /etc/init.d/denyhosts restart

Step Three—(Optional) Configure DenyHosts

DenyHosts is ready use as soon as the installation is over.

However if you want to customize the behavior of DenyHosts on your server, you can make the changes within the DenyHost configuration file:
# vim /etc/denyhosts.conf

 

Comments

Popular posts from this blog

CentOS / Redhat : Configure CentOS as a Software Router with two interfaces

Linux can be easily configured to share an internet connection using iptables. All you need to have is, two network interface cards as follows: a) Your internal (LAN) network connected via eth0 with static ip address 192.168.0.1 b) Your external WAN) network is connected via eth1 with static ip address 10.10.10.1  ( public IP provided by ISP ) Please note that interface eth1 may have public IP address or IP assigned by ISP. eth1 may be connected to a dedicated DSL / ADSL / WAN / Cable router: Step # 1: Enable Packet Forwarding Login as the root user. Open /etc/sysctl.conf file # vi /etc/sysctl.conf Add the following line to enable packet forwarding for IPv4: net.ipv4.conf.default.forwarding=1 Save and close the file. Restart networking: # service network restart Step # 2: Enable IP masquerading In Linux networking, Network Address Translation (NAT) or Network Masquerading (IP Masquerading) is a technique of transceivin

Virtual Box and Alt/Tab Keys

I use virtual box for all my testing activities. It comes too often that I have a virtual box VM window open & I want to switch to my host machine to see some stuff like tutorials etc.. If you press the alt+tab combination it just works inside the VM & doesn't switches to host machine. In these scenarios you can press the host key once ( not hold it ) & then whatever you press goes to host machine. So in general where host key is the default Right Ctrl, just press Right Ctrl once & now press the alt+tab & it will switch you out to host machine. This is really helpful when you have the VM windows open or you're working on seamless mode. Hope it help others too.

AMD Radeon™ HD 7670M on Ubuntu 12.04

Update:   Recently I install kubuntu 13.10 and there is no problem with graphics. It just works  fine out of the box. I've seen many blog posts on how to make AMD HD7670M work on Ubuntu 12.04, specially when its in switchable graphics board like Dell Inspiron 15R 5520. I tried many things to make it work so that I could use the cinnamon desktop on ubuntu & other things too.. But to my surprise even the drivers from AMD site didn't work. Then I tried a combination of those blog posts I read & somehow I became successful in running the full graphics including compiz settings inside My Ubuntu Machine. Following are the steps I followed & it worked... 1. Create a backup of your xorg configuration file: sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.BAK 2. Remove/purge current fglrx and fglrx-amdcccle : sudo apt-get remove --purge fglrx* 3. Install the driver: sudo apt-get install fglrx fglrx-amdcccle 4. Install additional