linux-lan

/etc/sysconfig/network-scripts
ifdown ifcfg-eth0
ifup
ifconfig
szexzdz

/etc/sysconfig/network[top] gateway

• NETWORKING=yes
• HOSTNAME=host.domainname.com ## set Host Name
• GATEWAY=20.0.0.254 && SET THE ROUTER'S GATEWAY

/etc/sysctl.conf[top]

net.ipv4.ip_forward=1 && 0 for disable routner, default is 0
net.ipv4.tcp_syncookies = 1 && prevents the Linux machine from sync flood attacks
net.ipv4.icmp_echo_ignore_broadcasts = 1 && prevents attackers make use smurf attacks.
kernel.shmmax = 5000000

/etc/sysconfig/network-scripts/ifcfg-eth0[top]

• DEVICE=eth0 &&eth0 it must match the file name , when second id, then the eth0, change to eth0:0
• BOOTPROTO =dhcp ii(dhcp , none, dhcp or static)
• HWADDR==00:12:34:56:78:90
• ONBOOT=yes && when linux boot up
• DHCP_HOSTNAME=servera.domain.com
• SEARCH=
• NM_CONTROLLED=
• IPADDR=192.168.65.31 && iif(dhcp, 192.168.65.31, no this line)
• NETMASK=255.255.255.0 && iif(dhcp, 255.255.255.0, no this line)
• GATEWAY=192.168.65.254 && iif(dhcp, 192.168.65.3254, no this line)

Remark : The Second will call ifcfg-eth1

/etc/resolv.conf ## DNS Setting

echo "nameserver 202.14.67.4" >> /etc/resolv.conf