Invoke the linuxconf tool. ( type linuxconf in the shell prompt and press Enter ). For starting this tool you have to be logged in as Super user. In the displayed menu, select the menu item : IP Aliases for virtual hosts and press Enter. This will display the two interfaces eth0 and lo. (Ethernet [...]

It is important to note that in FreeBSD (unlike linux) you will use the correct netmask for all IPs (even aliases) but with FreeBSD you will only need this once. After you have added the first IP the rest of the IPS (aliases) will use netmask 255.255.255.255. The following will guide you to how to [...]

Sometime it is necessary to block incoming connection or traffic from specific remote host. iptables is administration tool for IPv4 packet filtering and NAT under Linux kernel. Following tip will help you to block attacker or spammers IP address.  The blocklist is create with an API I wrote and you can use wget to update [...]

SquidGuard is a URL redirector and content filter addon that restricts proxy clients from accessing particular and/or banned site(s), IP addresses, URLs, website patterns using the proxy server.  SquidGuard can be used in conjunction with Squid proxy to implement website content filter from the proxy server. Here’s a run down on how to install and [...]

Most popular distro kernels ship with the bonding driver already available as a module and the ifenslave user level control program installed and ready for use. If your distro does not, or you have need to compile bonding from source (e.g., configuring and installing a mainline kernel from kernel.org), you’ll need to perform the following [...]

Memcached is a high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load. Memcached is a great piece of software that was designed with performance in mind. Still, memcached has little (or should I say none?) security features built-in. If we run [...]

Normally when you add a new IP to a network interface in a RedHat based system you create a file ifcfg-eth0:x in /etc/sysconfig/network-scripts/. For example: /etc/sysconfig/network-scripts/ifcfg-eth0:0 DEVICE=eth0:0 ONBOOT=yes BOOTPROTO=static IPADDR=192.168.0.100 NETMASK=255.255.255.0 NETWORK=192.168.0.0 BROADCAST=192.168.0.255 TYPE=Ethernet Similar to the above example you can create several aliases. But what if you have to add a lot of IPs [...]

PPTP is known to be less secure than other VPN software, but if you need a quick solution for a VPN server that will connect out of the box from Windows workstations PPTP is the obvious choice. This post will show how easy it is to setup a pptp vnp server on Debian Etch. A [...]

SmoothWall Express 2.0 is a free Linux-based firewall, which installs on a dedicated machine. Its interesting features include the ability to set up a DMZ for hosting the Web servers, FTP servers and an IDS (Intrusion Detection System) to protect your internal network. The firewall is also compatible with ISDN and ADSL and automatically senses [...]

With the growth of the Internet, e-mail has quickly become the main vehicle to spread information through the public at large. As the demand for fast, cheap and reliable e-mail grows, more individuals are turning to Linux to provide a fast, cheap and reliable solution. sendmail was originally developed by Eric Allman, in 1979, as [...]

Two commands: $ /sbin/ifconfig eth0:0 192.168.0.4 $ /sbin/route add -host 192.168.0.4 dev eth0:0 (replace that IP with the one you’d like to add) This change will no longer be in effect after rebooting. Therefor you must add the two commands to the bottom of your /etc/rc.local file. Your NIC should now be listening and responding [...]