Centos伺服器雙網卡IP不能同時被訪問的解決方案

環境簡述：

伺服器A具備雙網卡，安裝作業系統RHEL6.3

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網卡顯示名稱 IP地址 網關

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eth0 192.168.153.4 192.168.153.1

eth1 192.168.152.4 192.168.152.1

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網卡設定檔：

12345678910111213141516[root@clovem ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0DEVICE=eth0ONBOOT=yesBOOTPROTO=staticTYPE=EthernetIPADDR=192.168.153.4NETMASK=255.255.255.0GATEWAY=192.168.153.1[root@clovem ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth1DEVICE=eth1ONBOOT=yesBOOTPROTO=staticTYPE=EthernetIPADDR=192.168.152.4NETMASK=255.255.255.0GATEWAY=192.168.152.1

重啟網路服務

[root@clovem ~]# service network restart

查看其路由資訊：

[root@clovem ~]# route

Kernel IP routing table

Destination Gateway Genmask Flags Metric Ref Use Iface

192.168.153.0 * 255.255.255.0 U 0 0 0 eth0

192.168.152.0 * 255.255.255.0 U 0 0 0 eth1

link-local * 255.255.0.0 U 1015 0 0 eth0

link-local * 255.255.0.0 U 1016 0 0 eth1

default 192.168.152.1 255.255.255.0 UG 1017 0 0 eth1

可以發現雙網卡的預設閘道為192.168.152.1

從其他網段192.168.151.0/24的某台測試機:192.168.150.252

訪問192.168.153.4以及192.168.152.4 ,只能通過192.168.152.4進行網路連接，而192.168.153.4卻不可以，從上面的路由表中可以看出兩個網卡設定檔中的網關參數只有192.168.152.1生效，並被設定為預設閘道。

解決方案：

1.將兩個網卡設定檔中的GATEWAY參數全部刪除，即

1234567891011121314[root@clovem ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0DEVICE=eth0ONBOOT=yesBOOTPROTO=staticTYPE=EthernetIPADDR=192.168.153.4NETMASK=255.255.255.0[root@clovem ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth1DEVICE=eth1ONBOOT=yesBOOTPROTO=staticTYPE=EthernetIPADDR=192.168.152.4NETMASK=255.255.255.0

2. 重啟網路

[root@clovem ~]# service network restart

3.查看路由表

[root@clovem ~]# route

Kernel IP routing table

Destination Gateway Genmask Flags Metric Ref Use Iface

192.168.153.0 * 255.255.255.0 U 0 0 0 eth0

192.168.152.0 * 255.255.255.0 U 0 0 0 eth1

link-local * 255.255.0.0 U 1015 0 0 eth0

link-local * 255.255.0.0 U 1016 0 0 eth1

發現預設閘道沒有被設定

4. 添加靜態路由表

12345678[root@clovem ~]# echo "153 net_153" >> /etc/iproute2/rt_tables[root@clovem ~]# echo "152 net_152" >> /etc/iproute2/rt_tables[root@clovem ~]# ip route flush table net_153[root@clovem ~]# ip route add default via 192.168.153.1 dev eth0 src 192.168.153.4 table net_153[root@clovem ~]# ip rule add from 192.168.153.4 table net_153[root@clovem ~]# ip route flush table net_152[root@clovem ~]# ip route add default via 192.168.152.1 dev eth0 src 192.168.153.4 table net_152[root@clovem ~]# ip rule add from 192.168.152.4 table net_152

5. 此時再次通過正式發行前小眾測試機訪問均可

123456789[root@storage252 ~]# ifconfig eth0eth0 Link encap:Ethernet HWaddr 00:50:56:82:56:55inet addr:192.168.150.252 Bcast:192.168.150.255 Mask:255.255.255.0inet6 addr: fe80::250:56ff:fe82:5655/64Scope:LinkUP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1RX packets:25910143 errors:0 dropped:0 overruns:0 frame:0TX packets:19888495 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:1000RX bytes:26258149440 (24.4 GiB) TX bytes:16323278977 (15.2 GiB)1234567891011121314[root@storage252 ~]# ping -W1 -c2 192.168.152.4PING 192.168.152.4 (192.168.152.4) 56(84) bytes of data.64 bytes from 192.168.152.4: icmp_seq=1 ttl=63time=0.324 ms64 bytes from 192.168.152.4: icmp_seq=2 ttl=63time=0.349 ms--- 192.168.152.4pingstatistics ---2 packets transmitted, 2 received, 0% packet loss,time1000msrtt min/avg/max/mdev= 0.324/0.336/0.349/0.022 ms[root@storage252 ~]# ping -W1 -c2 192.168.153.4PING 192.168.153.4 (192.168.153.4) 56(84) bytes of data.64 bytes from 192.168.153.4: icmp_seq=1 ttl=63time=0.342 ms64 bytes from 192.168.153.4: icmp_seq=2 ttl=63time=0.271 ms--- 192.168.153.4pingstatistics ---2 packets transmitted, 2 received, 0% packet loss,time999msrtt min/avg/max/mdev= 0.271/0.306/0.342/0.039 ms

最後還需要添加一條預設閘道，才能讓該系統訪問其他網段主機

[root@clovem ~]#route add default gw 192.168.153.1

可以根據需要將靜態路由命令添加至相關設定檔，重啟之後仍然生效。