ROUTER

Pertama yang harus di lakukan adalah mensetting mgw(main gateway) supaya bisa connect ke internet
Sebelum Mensetting :

1.Minta IP public ke ISP lengkap dengan netmask,broadcast dan dns nya
misalnya :
RANGE : 202.159.121.0/29
IP : 202.159.121.2
GATEWAY : 202.159.121.1
Nemast : 255.255.255.248
broadcast : 202.159.121.7
DNS1 : 202.159.0.10
DNS2 : 202.159.0.20
berarti kita mendapatkan ip 5 buah dari 202.159.121.2 - 202.159.121.6

2.Menentukan IP local yang akan kita gunakan buat client

Setting IP MGW :
1.[root@mgw cachak]$ vi /etc/sysconfig/network
lalu isi dengan :

NETWORKING=yes
HOSTNAME=mgw.domain.com
GATEWAY=202.159.121.1

lalu simpen dengan menekan :wq

2.Menconfigurasi IP eth0(default)

[root@mgw root]$ vi /etc/sysconfig/network-scripts/ifcfg-eth...
lalu isi dengan :

DEVICE=eth0
BOOTPROTO=static
IPADDR=202.159.121.2
BROADCAST=202.159.121.7
NETMASK=255.255.255.249
ONBOOT=yes
USERCTL=no

lalu simpen dengan menekan :wq

3.Setting dns resolve

[root@mgw root]$ vi /etc/resolve.conf
lalu isi dengan nameserver dari isp kita tadi :

nameserver 202.159.0.10
nameserver 202.159.0.20

lalu simpen dengan menekan :wq

4.Setting ip_forwarding

[root@mgw cachak]$ vi /etc/sysctl.conf

rubah net.ipv4.ip_forward = 0 menjadi net.ipv4.ip_forward = 1
atau kalau gak ada net.ipv4.ip_forward = 0 tambahin net.ipv4.ip_forward = 1

simpen dengan menekan :wq

5.restart network
[root@mgw cachak]$ /etc/init.d/network restart
Shutting down interface eth0: [ OK ]
Shutting down loopback interface: [ OK ]
Disabling IPv4 packet forwarding: [ OK ]
Setting network parameters: [ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0: [ OK ]

[root@www root]#chkconfig –level 2345 network on
[root@www root]#

6.testing dengan ngeping ke default gateway 202.159.121.1

[root@mgw cachak]$ ping 202.159.121.1
PING 202.159.121.1 (202.159.121.1) 56(84) bytes of data.
64 bytes from 202.159.121.1: icmp_seq=1 ttl=63 time=0.356 ms
64 bytes from 202.159.121.1: icmp_seq=2 ttl=63 time=0.269 ms
64 bytes from 202.159.121.1: icmp_seq=3 ttl=63 time=0.267 ms
64 bytes from 202.159.121.1: icmp_seq=4 ttl=63 time=0.268 ms

— 202.159.121.1 ping statistics —
4 packets transmitted, 4 received, 0% packet loss, time 2997ms
rtt min/avg/max/mdev = 0.267/0.290/0.356/0.038 ms

7.testing untuk ngeping google.com untuk ngecek dns nya
kalau muncul :
PING google.com (216.239.39.99) 56(84) bytes of data.
berarti dns kita untuk mgw dah bekerja, tapi kalau muncul :
ping: unknown host google.com
berarti dns yang kita isikan di /etc/resolve.conf masih salah,silahkan cek lagi ke ISP nya )

nah bereskan sudah setting IP untuk mgw nya )
supaya mgw ini bisa sekaligus di gunakan sebagai ns server oleh client maka harus di install daemon bind atau daemon nameserver yang lain
ataukalau sudah ada tinggal idupin Bind nya

[root@www root]# /etc/init.d/named restart
Stopping named: [ OK ]
Starting named: [ OK ]
[root@www root]#chkconfig –level 2345 named on
[root@www root]#

misalnya ip ke client adalah :
192.168.0.1/24
IP : 192.168.0.1
netmask : 255.255.255.0
broadcast : 192.168.0.255
RANGE IP CLIENT : 192.168.0.2-192.168.0.254

Setting ip untuk eth1 (yang ke client)
1.memberi IP 192.168.0.1 di eth1
[root@mgw cachak]$ vi /etc/sysconfig/network-scripts/ifcfg-eth...
lalu isi dengan :

DEVICE=eth1
BOOTPROTO=static
IPADDR=192.168.0.1
NETMASK=255.255.255.0
BROADCAST=192.168.0.255
ONBOOT=yes
USERCTL=no

lalu simpen dengan menekan :wq

2.Restart networknya

[root@mgw root]$ /etc/init.d/network restart
Shutting down interface eth0: [ OK ]
Shutting down interface eth1: [ OK ]
Shutting down loopback interface: [ OK ]
Disabling IPv4 packet forwarding: [ OK ]
Setting network parameters: [ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0: [ OK ]
Bringing up interface eth1: [ OK ]

3.Testing dengan cara ping ip eth1
[root@mgw cachak]$ ping 192.168.0.1
PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data.
64 bytes from 192.168.0.1: icmp_seq=1 ttl=63 time=0.356 ms
64 bytes from 192.168.0.1: icmp_seq=2 ttl=63 time=0.269 ms
64 bytes from 192.168.0.1: icmp_seq=3 ttl=63 time=0.267 ms
64 bytes from 192.168.0.1: icmp_seq=4 ttl=63 time=0.268 ms

— 192.168.0.1 ping statistics —
4 packets transmitted, 4 received, 0% packet loss, time 2997ms
rtt min/avg/max/mdev = 0.267/0.290/0.356/0.038 ms

Tinggal Setting IP computer client dengan ketentuan di bawah ini :

IP : 192.168.0.2 - 192.168.0.254
GATEWAY : 192.168.0.1
NETMASK : 255.255.255.0
BROADCAST : 192.168.0.255
NAMESERVER : 192.168.0.1

misal :

Client01
===============================
IP : 192.168.0.2
GATEWAY : 192.168.0.1
NETMASK : 255.255.255.0
BROADCAST : 192.168.0.255
NAMESERVER : 192.168.0.1

Client02
===============================
IP : 192.168.0.3
GATEWAY : 192.168.0.1
NETMASK : 255.255.255.0