Configure Linux as a gateway

Reprinted:

Http://blog.csdn.net/zhangyang0402/archive/2010/06/25/5695050.aspx

 I. Network Topology

 

 

2. Configure the network

 

1.Network Configuration of A, gw1, gw2, and B

 

A:

Eth0:

Ipaddr: 192.168.1.2

Netmask: 255.255.255.0

Gateway: 192.168.1.1

 

Gw1:

Eth0:

Ipaddr: 172.16.113.173

Netmask: 255.255.255.0

Gateway: 172.16.113.9

 

Eth1:

Ipaddr: 192.168.1.1

Netmask: 255.255.255.0

 

B:

Eth0:

Ipaddr: 192.168.0.2

Netmask: 255.255.255.0

Gateway: 192.168.0.1

Gw2:

Eth0:

Ipaddr: 172.16.113.163

Netmask: 255.255.255.0

Gateway: 172.16.113.9

 

Eth1:

Ipaddr: 192.168.0.1

Netmask: 255.255.255.0

 

 

2.Gw1 settings

(1)Enable route forwarding

# Echo 1>/proc/sys/NET/IPv4/ip_forward

Or

# Vim/etc/sysctl. conf

Net. ipv4.ip _ forward = 0 --> net. ipv4.ip _ forward = 1

 

(2)Route entry added to CIDR Block 192.168.0.0/24

# Route add-net 192.168.0.0 netmask 255.255.255.0 GW 172.16.113.163

 

 

3.Gw2 settings

(1)Enable route forwarding

# Echo 1>/proc/sys/NET/IPv4/ip_forward

Or

# Vim/etc/sysctl. conf

Net. ipv4.ip _ forward = 0 --> net. ipv4.ip _ forward = 1

 

(2)Route entry added to 192.168.1.0/24 CIDR Block

# Route add-net 192.168.1.0 netmask 255.255.255.0 GW 172.16.113.173

 

Iii. Test Gateway

If a and B can ping each other, the two gateways are configured successfully.

 I. Network Topology

 

 

2. Configure the network

 

1.Network Configuration of A, gw1, gw2, and B

 

A:

Eth0:

Ipaddr: 192.168.1.2

Netmask: 255.255.255.0

Gateway: 192.168.1.1

 

Gw1:

Eth0:

Ipaddr: 172.16.113.173

Netmask: 255.255.255.0

Gateway: 172.16.113.9

 

Eth1:

Ipaddr: 192.168.1.1

Netmask: 255.255.255.0

 

B:

Eth0:

Ipaddr: 192.168.0.2

Netmask: 255.255.255.0

Gateway: 192.168.0.1

Gw2:

Eth0:

Ipaddr: 172.16.113.163

Netmask: 255.255.255.0

Gateway: 172.16.113.9

 

Eth1:

Ipaddr: 192.168.0.1

Netmask: 255.255.255.0

 

 

2.Gw1 settings

(1)Enable route forwarding

# Echo 1>/proc/sys/NET/IPv4/ip_forward

Or

# Vim/etc/sysctl. conf

Net. ipv4.ip _ forward = 0 --> net. ipv4.ip _ forward = 1

 

(2)Route entry added to CIDR Block 192.168.0.0/24

# Route add-net 192.168.0.0 netmask 255.255.255.0 GW 172.16.113.163

 

 

3.Gw2 settings

(1)Enable route forwarding

# Echo 1>/proc/sys/NET/IPv4/ip_forward

Or

# Vim/etc/sysctl. conf

Net. ipv4.ip _ forward = 0 --> net. ipv4.ip _ forward = 1

 

(2)Route entry added to 192.168.1.0/24 CIDR Block

# Route add-net 192.168.1.0 netmask 255.255.255.0 GW 172.16.113.173

 

Iii. Test Gateway

If a and B can ping each other, the two gateways are configured successfully.