CentOS 實作 2 WAN

q我的 Server 背板位置

• 將實際網路位置、MAC與CentOS 作業系統的NICs 名稱完成對應(以下是在ESXi上實現，故多了一層對應)

  vmnic	MAC	Func Name	Network Adapter	MAC (vmOS)	eth name	IP-Address	說明
  0	xx:40	M1	1	78	eth0	10.20.13.101/24 GW:10.20.13.1	接WAN1的Router LAN
  1	xx:41	M2	2	82	eth1	10.21.13.101/24 GW:10.21.13.1	接WAN2的Router LAN
  2	xx:67	MC	3	8c	eth2	10.30.13.100/24
  3	xx:98	ST	4	96	eth3	10.40.13.101/24
  4	xx:99	x	x	x	x	x

  
  
  
• 永久停用 NetworkManager

chkconfig NetworkManager offservice NetworkManager stop

# 重啟網路 #
service network restart

• 永久關閉防火牆

chkconfig –level 35 iptables off/etc/init.d/iptables stopiptables –P INPUT DROP

•  ##Create 2 route table, only fist time need execute bellow command: echo “wan1” >> /etc/iproute2/rt_tables
  echo “wan2” >> /etc/iproute2/rt_tables
  PS: 檔案 /etc/iproute2/rt_tables 將增加兩行如下圖
  
  
• 修改 檔案 /etc/rc.d/rc.local 讓開機時自動建立雙WAN
  
  修改前:
  
  加入指令:

     1: ##Add routing ip address write to routing table. 

  
  

     2: ##Add route table of wan2

  
  

     3: ip route add 10.21.13.0/24 dev eth1 src 10.21.13.101 table wan2

  
  

     4: ip route add 127.0.0.1/8 dev lo scope link table wan2

  
  

     5: ip route add default via 10.21.13.1 dev eth1 table wan2

  
  

     6:  

  
  

     7: ##Add route table of wan1

  
  

     8: ip route add 10.20.13.0/24 dev eth0 src 10.20.13.101 table wan1

  
  

     9: ip route add 127.0.0.1/8 dev lo scope link table wan1

  
  

    10: ip route add default via 10.20.13.1 dev eth0 table wan1

  
  

    11:  

  
  

    12: ##Add rule to route table wan1 and wan2:

  
  

    13: ip rule add from 10.21.13.101 table wan2

  
  

    14: ip rule add from 10.20.13.101 table wan1

  
  

    15:  

  
  

    16: ##Replace default route ip address.

  
  

    17: ip route add default scope global nexthop via 10.20.13.1 dev eth0 weight 1 nexthop via 10.21.13.1 dev eth1 weight 1

  
  

    18:  

• 設定DNS

ping google.com.tw

無回應時，代表沒設定DNS

互動試設定指令 :  system-config-network

參考文章 : CentOS 基礎設定（上）