Files related to networking functionality
# Enable packet forwarding net.ipv4.ip_forward = 1
You must restart your network for the change to take effect. The command to restart the network is the following:
• To restart all network devices manually on your system, use the following command: [root@deep /]# /etc/rc.d/init.d/network restart
Setting network parameters [ OK ]
Bringing up interface lo [ OK ]
Bringing up interface ethO [ OK ]
Bringing up interface eth1 [ OK ]
NOTE: Enabling IPv4 forwarding via the sysctl.conf file is only valid for Red Hat Linux 6.2 users. Users with version 6.1 of Red Hat must set this parameter into the 7etc/sysconfig/network” file as explained above.
The “/etc/hosts” file
As your machine gets started, it will need to know the mapping of some hostnames to IP addresses before DNS can be referenced. This mapping is kept in the “/etc/hosts” file. In the absence of a name server, any network program on your system consults this file to determine the IP address that corresponds to a host name.
Following is a sample “/etc/hosts” file:
| IP Address | Hostname | Alias |
| 127.0.0.1 | localhost | deep.openna.com |
| 208.164.186.1 | deep.openna.com | deep |
| 208.164.186.2 | mail.openna.com | |
| 208.164.186.3 | web.openna.com | web |