Load Balancing di Linux

Install Router Load Balancing di Ubuntu

• insert ubuntu disc
• boot

Selanjutnya install a command line system

Login ke system yang baru kita install. Lakukan sudo root.

$ sudo passwd root

# su -

Edit IP address interface

# vi /etc/network/interfaces
     auto eth0
     iface eth0 inet static
           address 10.0.148.48
           netmask 255.255.255.0
     auto eth1
     iface eth1 inet static
           address 192.168.0.222
           netmask 255.255.255.0
     auto eth2
     iface eth2 inet static
           address 192.168.1.222
           netmask 255.255.255.0

Ubah sources.list agar sesuai dengan sumber software Ubuntu yang kita inginkan.

# vi /etc/apt/source-list
     deb ftp://192.168.0.1/pub/edgy-repo1/ edgy main restricted
     deb ftp://192.168.0.1/pub/edgy-repo2/ edgy universe
     deb ftp://192.168.0.1/pub/edgy-repo3/ edgy universe
     deb ftp://192.168.0.1/pub/edgy-repo4/ edgy universe multiverse 
# apt-get update

Install openssh server agak dapat melakukan remore login

# apt-get install openssh-server
# /etc/init.d/ssh restart

Ubah timezone agar sesuai dengan daerah anda

# vi /etc/timezone
     Asia/Jakarta

Setup iproute2

Agar saat nanti di booting tetap ada, masukan perintah-perintah ini ke shell script dan masukan ke /etc/rc.local

/sbin/ip link set lo up
/sbin/ip link set eth0 up
/sbin/ip link set eth1 up
/sbin/ip link set eth2 up

/sbin/ip route flush table adsl
/sbin/ip route flush table rtrwnet
/sbin/ip route flush table internet

/sbin/ip addr add 127.0.0.1/8 brd 127.0.0.255 dev lo

/sbin/ip addr add 192.168.1.222/24 brd 192.168.1.255 dev eth2
# /sbin/ip addr add 10.0.148.48/24 brd 10.0.148.255 dev eth0
/sbin/ip addr add 192.168.0.222/24 brd 192.168.0.255 dev eth1

/sbin/ip route add 127.0.0.0/8 dev lo
/sbin/ip route add 10.5.148.0/24 via 10.0.148.254 dev eth0
/sbin/ip route add 192.168.0.0/24 dev eth1
/sbin/ip route add 44.132.33.0/24 via 192.168.0.10 dev eth1
/sbin/ip route add 192.168.11.0/24 via 192.168.0.10 dev eth1
/sbin/ip route add 125.160.6.0/24 via 192.168.1.1 dev eth2
/sbin/ip route add 202.159.32.0/24 via 192.168.1.1 dev eth2

/sbin/ip rule add prio 10 table main
/sbin/ip rule add prio 20 table adsl
/sbin/ip rule add prio 30 table rtrwnet
/sbin/ip rule add prio 40 table internet

/sbin/ip route del default table main
/sbin/ip route del default table adsl
/sbin/ip route del default table rtrwnet
/sbin/ip route del default table internet

/sbin/ip rule add prio 20 from 192.168.1.0/24 table adsl
/sbin/ip route add default via 192.168.1.1 dev eth2 src 192.168.1.222 proto static table adsl
/sbin/ip route append prohibit default table adsl metric 1 proto static

/sbin/ip rule add prio 30 from 10.0.148.0/24 table rtrwnet
/sbin/ip route add default via 10.0.148.254 dev eth0 src 10.0.148.48 proto static table rtrwnet
/sbin/ip route append prohibit default table rtrwnet metric 5 proto static

# Set up load balancing gateways
/sbin/ip rule add prio 40 table internet
/sbin/ip route add default proto static table internet \
       nexthop via 192.168.1.1 dev eth2 weight 1 \
       nexthop via 10.0.148.254 dev eth0 weight 10

# Setup routing to ISPs
/sbin/ip route add 202.138.236.0/24 proto static table internet \
       nexthop via 192.168.1.1 dev eth2 weight 10 \
       nexthop via 10.0.148.254 dev eth0 weight 1

Setup iptables

Agar saat nanti di booting tetap ada, masukan perintah-perintah ini ke shell script dan masukan ke /etc/rc.local

/bin/echo 1 > /proc/sys/net/ipv4/ip_forward

/sbin/iptables -F
/sbin/iptables -P INPUT DROP
/sbin/iptables -A INPUT -p tcp -i eth1 --destination-port 25 -s ! 192.168.0.1  -j DROP

/sbin/iptables -A INPUT -i eth1 -j ACCEPT
/sbin/iptables -A INPUT -i eth0 -p tcp -s 0/0 --dport 25 -j ACCEPT
/sbin/iptables -A INPUT -i eth2 -p tcp -s 0/0 --dport 25 -j ACCEPT
/sbin/iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
/sbin/iptables -A INPUT -p tcp -i eth0 -j REJECT --reject-with tcp-reset
/sbin/iptables -A INPUT -p tcp -i eth2 -j REJECT --reject-with tcp-reset
/sbin/iptables -A INPUT -p udp -i eth0 -j REJECT --reject-with icmp-port-unreachable
/sbin/iptables -A INPUT -p udp -i eth2 -j REJECT --reject-with icmp-port-unreachable

/sbin/iptables -t nat -A POSTROUTING -o eth2 -j SNAT --to 192.168.1.222
/sbin/iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to 10.0.148.48

Setup /etc/iproute2/rt_tables

120     adsl
121     rtrwnet
123     internet