A) Temporary setting of IP address (until next Linux restart).
Just add the following two commands for settings of IP/mask and default gateway:
ifconfig eth0 192.168.1.100 netmask 255.255.255.0 # setting of IP address and mask
route add default gw 192.168.1.12 # setting of default gateway
route add default gw 192.168.1.12 # setting of default gateway
B) Permanent setting of IP address
Modify the current IP address to the one you want:
nano /etc/rc.local
nano /etc/hosts
nano /etc/apache2/httpd.conf
reboot -f # system restart
nano /etc/hosts
nano /etc/apache2/httpd.conf
reboot -f # system restart