The Perfect Server - CentOS 5.2 - Page 3
4 Adjust /etc/hosts
Next we edit /etc/hosts. Make it look like this:
5 Configure Additional IP Addresses
(This section is totally optional. It just shows how to add additional IP addresses to your network interface eth0 if you need more than one IP address. If you're fine with one IP address, you can skip this section.)
Let's assume our network interface is eth0. Then there is a file /etc/sysconfig/network-scripts/ifcfg-eth0 which contains the settings for eth0. We can use this as a sample for our new virtual network interface eth0:0:
cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0:0
Now we want to use the IP address 192.168.0.101 on the virtual interface eth0:0. Therefore we open the file /etc/sysconfig/network-scripts/ifcfg-eth0:0 and modify it as follows (we can leave out the HWADDR line as it is the same physical network card):
Afterwards we have to restart the network:
You might also want to adjust /etc/hosts after you have added new IP addresses, although this is not necessary.
You should now see your new IP address in the output:
[root@server1 ~]# ifconfig
6 Disable The Firewall And SELinux
(You can skip this chapter if you have already disabled the firewall and SELinux at the end of the basic system installation (in the Setup Agent).)
I want to install ISPConfig at the end of this tutorial which comes with its own firewall. That's why I disable the default CentOS firewall now. Of course, you are free to leave it on and configure it to your needs (but then you shouldn't use any other firewall later on as it will most probably interfere with the CentOS firewall).
SELinux is a security extension of CentOS that should provide extended security. In my opinion you don't need it to configure a secure system, and it usually causes more problems than advantages (think of it after you have done a week of trouble-shooting because some service wasn't working as expected, and then you find out that everything was ok, only SELinux was causing the problem). Therefore I disable it, too (this is a must if you want to install ISPConfig later on).
Set both Security Level and SELinux to Disabled and hit OK:
Afterwards we must reboot the system:
7 Install Some Software
First we import the GPG keys for software packages:
rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY*
Then we update our existing packages on the system:
Now we install some software packages that are needed later on:
yum install fetchmail wget bzip2 unzip zip nmap openssl lynx fileutils ncftp gcc gcc-c++