快速設置Linux路由腳本

作者：佚名 2010-01-13 11:05:24

路由路由腳本自動切換網關，通過ping判斷網關的是否存活，來決定切換網關，路由腳本雛形:[root@stu86 lianxi]# cat roswap.sh

一、高級路由

路由路由腳本自動切換網關，通過ping判斷網關的是否存活，來決定切換網關
路由腳本雛形:
[root@stu86 lianxi]# cat roswap.sh
#!/bin/bash
while :                                                ＃死循環
do                                                     ＃做下面的事情
        route del default                              ＃刪除以前的默認網關配置
        route add default dev ppp0 gw 1.1.1.1          ＃添加一條網關

        while ping -c 1 1.1.1 &> /dev/null             ＃再次進入子循環里面，ping成功也就是為真的話，那么就循環，ping失敗跳出循環
        do
                sleep 1                                ＃ping通后，睡1秒
        done
        route del default                              ＃如果ping不通，來到這個語句。就刪除前面ppp0的網關地址
        route add default dev ppp1 gw 2.2.2.2          ＃并且用添加ppp1網關
        while ! ping -c 1.1.1.1 &> /dev/null           ＃如果ping不通則為真，ping通跳出循環。繼續從上開始了
        do
                sleep 1
        done
done
[root@stu86 lianxi]#

根據上面路由腳本改進：使用變量是路由腳本可用性提高
[root@stu86 lianxi]# cat roswap.sh
#!/bin/bash

ISP1=1.1.1.1                                            ＃定義變量IP
ISP2=2.2.2.2                                            ＃定義變量IP
$DEV1=ppp0                                              ＃定義接口
$DEV2=ppp1                                              ＃定義接口
$TIME=1                                                 ＃定義時間，以后改路由腳本只要改這些參數就可以了，不用改路由腳本內容很方便

while :
do
route del default
route add default dev $DEV1 gw $ISP1

        while ping -c $ISP1 &> /dev/null
        do
                sleep $TIME
        done
        route del default
        route add default dev $DEV2 gw $ISP2
        while ! ping -c 1 $ISP1 &> /dev/null
        do
                sleep $TIME
        done
done
[root@stu86 lianxi]#

二、網絡常用命令
[root@stu86 lianxi]# ifconfig
eth0      Link encap:Ethernet HWaddr 00:19:21:71:17:67
          inet addr:192.168.0.86 Bcast:192.168.0.255 Mask:255.255.255.0
          inet6 addr: fe80::219:21ff:fe71:1767/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:4123 errors:0 dropped:0 overruns:0 frame:0
          TX packets:61 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000                        ＃tc中limit大于1000值沒有意義的，tc的作用也是在這個上。物理的只支持1000

[root@stu86 lianxi]# route -n                                 ＃按照越精確越靠前。這個是路由的排序規則
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.179.0   0.0.0.0         255.255.255.0   U     0      0        0 vmnet1
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0
172.16.122.0    0.0.0.0         255.255.255.0   U     0      0        0 vmnet8
169.254.0.0     0.0.0.0         255.255.0.0     U     0      0        0 eth0

[root@stu86 lianxi]# route add -net 172.16.0.0 netmask 255.255.0.0 dev eth0          ＃添加網段路由
[root@stu86 lianxi]# route add -host 172.16.1.1 dev eth0                             ＃添加主機路由
[root@stu86 lianxi]# route del -net 172.16.0.0 netmask 255.255.0.0 dev eth0          ＃刪除網段路由
[root@stu86 lianxi]# route del -host 172.16.1.1 dev eth0                             ＃刪除主機路由

[root@stu86 lianxi]# netstat -a|less                                                 ＃查看所有并分屏顯示
[root@stu86 lianxi]# netstat -i                                                      ＃查看網卡詳細信息
Kernel Interface table
Iface       MTU Met    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eth0       1500   0     4652      0      0      0       61      0      0      0 BMRU
lo        16436   0     1679      0      0      0     1679      0      0      0 LRU
vmnet1     1500   0        0      0      0      0       48      0      0      0 BMRU
vmnet8     1500   0        0      0      0      0       50      0      0      0 BMRU
[root@stu86 lianxi]#

[root@stu86 lianxi]# netstat -r                                                     ＃查看路由表和route －n一樣
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window irtt Iface
192.168.179.0   *               255.255.255.0   U         0 0          0 vmnet1
192.168.0.0     *               255.255.255.0   U         0 0          0 eth0
172.16.122.0    *               255.255.255.0   U         0 0          0 vmnet8
169.254.0.0     *               255.255.0.0     U         0 0          0 eth0

三、網絡命令2版將替換unix上的命令
[root@stu86 lianxi]# rpm -q iproute ＃IProute的第二版，可以用IP命令
iproute-2.6.18-9.el5

1）ip＝ifconfig
[root@stu86 lianxi]# ip link show                                                ＃ip命令顯示ip鏈路層，更加詳細
1: lo: mtu 16436 qdisc noqueue
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth1: mtu 1500 qdisc noop qlen 1000
    link/ether 00:ee:ee:00:0a:76 brd ff:ff:ff:ff:ff:ff
3: eth0: mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:19:21:71:17:67 brd ff:ff:ff:ff:ff:ff
4: sit0: mtu 1480 qdisc noop
    link/sit 0.0.0.0 brd 0.0.0.0
5: vmnet1: mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:50:56:c0:00:01 brd ff:ff:ff:ff:ff:ff
6: vmnet8: mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:50:56:c0:00:08 brd ff:ff:ff:ff:ff:ff
[root@stu86 lianxi]#

[root@stu86 lianxi]# ip ad sh dev eth0                                          ＃ip命令查看網絡層的ip地址
3: eth0: mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:19:21:71:17:67 brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.86/24 brd 192.168.0.255 scope global eth0
    inet6 fe80::219:21ff:fe71:1767/64 scope link
       valid_lft forever preferred_lft forever

[root@stu86 lianxi]# ip route show ＃ip命令查看路由
192.168.179.0/24 dev vmnet1 proto kernel scope link src 192.168.179.1
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.86
172.16.122.0/24 dev vmnet8 proto kernel scope link src 172.16.122.1
169.254.0.0/16 dev eth0 scope link

四、更改IP地址
更改：先down在up
[root@stu86 lianxi]# ip link help                                               ＃查ip幫組
Usage: ip link set DEVICE { up | down |
                             arp { on | off } |
                             dynamic { on | off } |
                             multicast { on | off } |
                             allmulticast { on | off } |
                             promisc { on | off } |
                             trailers { on | off } |
                             txqueuelen PACKETS |
                             name NEWNAME |
                             address LLADDR | broadcast LLADDR |
                             mtu MTU }
       ip link show [ DEVICE ]
[root@stu86 lianxi]# ip link show dev eth0                                       ＃查看eth0
3: eth0: mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:19:21:71:17:67 brd ff:ff:ff:ff:ff:ff
[root@stu86 lianxi]# ip link set dev eth0 down                                   ＃關閉eth0
[root@stu86 lianxi]# ip link set dev eth0 address 00:99:88:77:66:55              ＃更改mac地址
[root@stu86 lianxi]# ip link set dev eth0 up                                     ＃啟動eth0

改ip地址：
[root@stu86 lianxi]# ip address add dev eth0 172.16.0.222/24                     ＃添加ip
[root@stu86 lianxi]# ip address show dev eth0                                    ＃查看eth0IP
3: eth0: mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:19:21:71:17:67 brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.86/24 brd 192.168.0.255 scope global eth0
    inet 172.16.0.222/24 scope global eth0
    inet6 fe80::219:21ff:fe71:1767/64 scope link
       valid_lft forever preferred_lft forever

[root@stu86 lianxi]# ip address del dev eth0 172.16.0.222/24 ＃刪除IP
注意：如果要換IP地址，那么就要把原來的IP刪除，然后添加一個新IP地址

五、IP路由
[root@stu86 lianxi]# ip route add default dev eth0 via 192.168.0.254           ＃添加默認路由
[root@stu86 lianxi]# ip route del default dev eth0 via 192.168.0.254           ＃刪除默認路由
[root@stu86 lianxi]# ip route add dev eth0 10.0.0.1/32                         ＃添加主機路由
[root@stu86 lianxi]# ip route del dev eth0 10.0.0.1/32                         ＃刪除主機路由
[root@stu86 lianxi]# ip route add dev eth0 192.168.0.0/16                      ＃添加網段路由
[root@stu86 lianxi]# ip route del dev eth0 192.168.0.0/16                      ＃刪除網段路由
[root@stu86 lianxi]# ip route show dev eth0                                    ＃查看路由信息
192.168.0.0/24 proto kernel scope link src 192.168.0.86

ss命令                                                                                                                                                   ＃和netstat命令差不多
[root@stu86 lianxi]# ss -antlp
[root@stu86 lianxi]# ip route help
Usage: ip route { list | flush } SELECTOR
       ip route get ADDRESS [ from ADDRESS iif STRING ]
                            [ oif STRING ] [ tos TOS ]
       ip route { add | del | change | append | replace | monitor } ROUTE
SELECTOR := [ root PREFIX ] [ match PREFIX ] [ exact PREFIX ]
            [ table TABLE_ID ] [ proto RTPROTO ]
            [ type TYPE ] [ scope SCOPE ]
ROUTE := NODE_SPEC [ INFO_SPEC ]
NODE_SPEC := [ TYPE ] PREFIX [ tos TOS ]
             [ table TABLE_ID ] [ proto RTPROTO ]
             [ scope SCOPE ] [ metric METRIC ]
             [ mpath MP_ALGO ]
INFO_SPEC := NH OPTIONS FLAGS [ nexthop NH ]...
NH := [ via ADDRESS ] [ dev STRING ] [ weight NUMBER ] NHFLAGS
OPTIONS := FLAGS [ mtu NUMBER ] [ advmss NUMBER ]
           [ rtt TIME ] [ rttvar TIME ]
           [ window NUMBER] [ cwnd NUMBER ] [ initcwnd NUMBER ]
           [ ssthresh NUMBER ] [ realms REALM ]
           [ rto_min TIME ]
TYPE := [ unicast | local | broadcast | multicast | throw |
          unreachable | prohibit | blackhole | nat ]
TABLE_ID := [ local | main | default | all | NUMBER ]
SCOPE := [ host | link | global | NUMBER ]
FLAGS := [ equalize ]
MP_ALGO := { rr | drr | random | wrandom }
NHFLAGS := [ onlink | pervasive ]
RTPROTO := [ kernel | boot | static | NUMBER ]
TIME := NUMBER[s|ms|us|ns|j]

六、作ECMP，一個命令添加等值多路路由
[root@stu86 lianxi]# ip route add default mpath rr \ ＃添加路由
> nexthop dev eth0 via 192.168.0.254 weight 10 \ ＃添加eth0的路由c
> nexthop dev eth1 via 10.0.0.10 weight 10
用路由腳本添加等值多路路由：
[root@stu86 lianxi]# vim ecmp.sh
[root@stu86 lianxi]# cat ecmp.sh
#!/bin/bash

ISP1=""
ISP2=""
#ISPN=""....

DEV1=""
DEV2=""
#DEVn="".....

DEL="ip route del default"
ADD="ip route add default"

$DEL
$ADD nexthop dev $DEV1 via $ISP1 weight 10 \
nexthop dev $DEV2 via $ISP2 weight 10

# nexthop dev $DEVn via $ISPn weight n .....
[root@stu86 lianxi]#

到控制臺中
[root@stu86 lianxi]# cd /usr/src/kernels/2.6.18-128.el5-i686/
[root@stu86 2.6.18-128.el5-i686]# make menuconfig
IP:equal cost multipath 在內核中選上，才支持ecmp。這個就叫做等值多路。

七、ip路由查看命令，分為main、default、local
[root@stu86 lianxi]# ip route show                                             ＃只能查看部分路由
192.168.179.0/24 dev vmnet1 proto kernel scope link src 192.168.179.1
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.86
172.16.122.0/24 dev vmnet8 proto kernel scope link src 172.16.122.1
[root@stu86 lianxi]# ip route show table all                                   ＃linux有很多路由表
192.168.179.0/24 dev vmnet1 proto kernel scope link src 192.168.179.1
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.86
172.16.122.0/24 dev vmnet8 proto kernel scope link src 172.16.122.1
broadcast 192.168.0.255 dev eth0 table 255 proto kernel scope link src 192.168.0.86
broadcast 127.255.255.255 dev lo table 255 proto kernel scope link src 127.0.0.1
broadcast 172.16.122.255 dev vmnet8 table 255 proto kernel scope link src 172.16.122.1
broadcast 192.168.179.255 dev vmnet1 table 255 proto kernel scope link src 192.168.179.1
broadcast 192.168.0.0 dev eth0 table 255 proto kernel scope link src 192.168.0.86
local 172.16.122.1 dev vmnet8 table 255 proto kernel scope host src 172.16.122.1
broadcast 172.16.122.0 dev vmnet8 table 255 proto kernel scope link src 172.16.122.1
broadcast 192.168.179.0 dev vmnet1 table 255 proto kernel scope link src 192.168.179.1
local 192.168.179.1 dev vmnet1 table 255 proto kernel scope host src 192.168.179.1
local 192.168.0.86 dev eth0 table 255 proto kernel scope host src 192.168.0.86
broadcast 127.0.0.0 dev lo table 255 proto kernel scope link src 127.0.0.1
local 127.0.0.1 dev lo table 255 proto kernel scope host src 127.0.0.1
local 127.0.0.0/8 dev lo table 255 proto kernel scope host src 127.0.0.1
fe80::/64 dev vmnet1 metric 256 expires 21323638sec mtu 1500 advmss 1440 hoplimit 4294967295
fe80::/64 dev vmnet8 metric 256 expires 21323638sec mtu 1500 advmss 1440 hoplimit 4294967295
fe80::/64 dev eth0 metric 256 expires 21330502sec mtu 1500 advmss 1440 hoplimit 4294967295
unreachable default dev lo table unspec proto none metric -1 error -101 hoplimit 255
local ::1 via :: dev lo table 255 proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295
local fe80::219:21ff:fe71:1767 via :: dev lo table 255 proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295
local fe80::250:56ff:fec0:1 via :: dev lo table 255 proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295
local fe80::250:56ff:fec0:8 via :: dev lo table 255 proto none metric 0 mtu 16436 advmss 16376 hoplimit 4294967295
ff02::fb via ff02::fb dev eth0 metric 0
    cache mtu 1500 advmss 1440 hoplimit 4294967295
ff00::/8 dev vmnet1 table 255 metric 256 expires 21323638sec mtu 1500 advmss 1440 hoplimit 4294967295
ff00::/8 dev vmnet8 table 255 metric 256 expires 21323638sec mtu 1500 advmss 1440 hoplimit 4294967295
ff00::/8 dev eth0 table 255 metric 256 expires 21330502sec mtu 1500 advmss 1440 hoplimit 4294967295
unreachable default dev lo table unspec proto none metric -1 error -101 hoplimit 255

[root@stu86 lianxi]# ip route show table main ＃我們通常查看main表
192.168.179.0/24 dev vmnet1 proto kernel scope link src 192.168.179.1
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.86
172.16.122.0/24 dev vmnet8 proto kernel scope link src 172.16.122.1
[root@stu86 lianxi]# ip route show table local ＃查看本地的路由表
broadcast 192.168.0.255 dev eth0 proto kernel scope link src 192.168.0.86
broadcast 127.255.255.255 dev lo proto kernel scope link src 127.0.0.1
broadcast 172.16.122.255 dev vmnet8 proto kernel scope link src 172.16.122.1
broadcast 192.168.179.255 dev vmnet1 proto kernel scope link src 192.168.179.1
broadcast 192.168.0.0 dev eth0 proto kernel scope link src 192.168.0.86
local 172.16.122.1 dev vmnet8 proto kernel scope host src 172.16.122.1
broadcast 172.16.122.0 dev vmnet8 proto kernel scope link src 172.16.122.1
broadcast 192.168.179.0 dev vmnet1 proto kernel scope link src 192.168.179.1
local 192.168.179.1 dev vmnet1 proto kernel scope host src 192.168.179.1
local 192.168.0.86 dev eth0 proto kernel scope host src 192.168.0.86
broadcast 127.0.0.0 dev lo proto kernel scope link src 127.0.0.1
local 127.0.0.1 dev lo proto kernel scope host src 127.0.0.1
local 127.0.0.0/8 dev lo proto kernel scope host src 127.0.0.1

八、實驗對標記1走路由表1，標記2走路由表2
定義策略路由表，通過策略屬性定義包的流向

1）添加2個表
[root@stu86 lianxi]# vim /etc/iproute2/rt_tables                          ＃定義有多少路由表
#
# reserved values
#
255     local
254     main            ＃默認查看的是main表
253     default
10      table1
20      table2
0       unspec          ＃未定義
#
# local
#
#1      inr.ruhep

2）添加兩個轉發表項，必須需要基于那條網段路由，才可以添加這個所在網段的默認網關
[root@stu86 lianxi]# route add default dev eth0 gw 192.168.0.254 ＃需要基于mian表才可以添加下面的內容

[root@stu86 lianxi]# ip route add table table1 192.168.0.0/24 dev eth0 ＃添加一個網段路由表交給eth0
[root@stu86 lianxi]# ip route add table table1 default dev eth0 via 192.168.0.254 ＃添加默認網關為254

[root@stu86 lianxi]# ip route add table table2 10.0.0.0/8 dev eth1 ＃添加一個網段路由表交給eht1
[root@stu86 lianxi]# ip route add table default dev eth1 via 10.0.0.1 ＃添加默認網關為1

[root@stu86 lianxi]# ip rule show ＃查看當前默認路由策略
0: from all lookup 255 ＃數越小優先級越高，0 為最高
32766: from all lookup main
32767: from all lookup default

方法1。基于ip
添加ip查看那個路由表
[root@stu86 lianxi]# for count in `seq 1 100` ;do ip rule add from 192.168.0.$count table table1;done ＃為每個IP添加路由腳本規則
[root@stu86 lianxi]# for count in `seq 101 254` ;do ip rule add from 192.168.0.$count table table2;done ＃為每個IP添加路由腳本規則
[root@stu86 lianxi]# ip rule show
0: from all lookup 255
32512: from 192.168.0.254 lookup table2

方法2。基于hash算法和防火墻標記的
優化問題：通過FBI（x）hash算法查詢。
我們可以把防火墻標記效率更高
如下：
[root@stu86 lianxi]# ip rule add fwmark 1 (pref 1000) table table1
[root@stu86 lianxi]# ip rule add fwmark 2 (pref 2000) table table2
打標記，需要在路由表前打標記
[root@stu86 lianxi]# iptables -t mangle -A PREROUTING -m iprange --src-range 192.168.0.1-192.168.0.100 -j MARK --set-mark 1 ＃標記ip范圍
[root@stu86 lianxi]# iptables -t mangle -A PREROUTING -m iprange --src-range 192.168.0.101-192.168.0.254 -j MARK --set-mark 2 ＃打標記

九、通過添加一個網段的指定路由優先級優化路由的策略
目標地址控制，上網
[root@stu86 lianxi]# ip ru sh
0: from all lookup 255
32764: from all fwmark 0x2 lookup table2
32765: from all fwmark 0x1 lookup table1
32766: from all lookup main
32767: from all lookup default
[root@stu86 lianxi]# ip rule del fwmark 1
[root@stu86 lianxi]# ip rule del fwmark 2

添加規則有順序，現允許部分，我們可以通過添加優先級來改變規則的順序。
[root@stu86 lianxi]# ip rule add from 192.168.0.0/24 to 1.1.1.1 table table1 prio 1000 ＃添加192的網段走1。1。1。1使用table1表，優先級為1000
[root@stu86 lianxi]# ip rule add table table2 prio 1100                   ＃其他所有的使用table2表，優先級為1100，相隔一定距離有利于以后添加規則
[root@stu86 lianxi]# ip rule show
0:      from all lookup 255
1000:   from 192.168.0.0/24 to 1.1.1.1 lookup table1
1100:   from all lookup table2
32766: from all lookup main
32767: from all lookup default

十、多線接入
多線解決方案
[root@stu86 lianxi]# echo $[RANDOM%255+1].$[RANDOM%256].$[RANDOM%256].$[RANDOM%254+1] ＃產生隨即IP地址
[root@stu86 lianxi]# for i in `seq 1 1000`;do echo $[RANDOM%255+1].$[RANDOM%256].$[RANDOM%256].$[RANDOM%254+1];done > /tmp/tel.txt ＃產生一千個隨機IP地址
echo $[RANDOM]：取隨機值
echo $[RANDOM%255+1]：取隨值并且取模余運算，這里是255，也就是余數范圍是從0開始到254結束一共255數字，這里加1目的防止ip地址第一位為0

優先級映射問題：人多的地方優化，使用人少的地方就算了
[root@stu86 lianxi]# sed 's/^.*$/cnc &/g' /tmp/cnc.txt >cnc.txt ＃給cnc文件打上標記，是個替換路由腳本
[root@stu86 lianxi]# sed 's/^.*$/tel &/g' /tmp/tel.txt >tel.txt ＃給tel文件打上標記，是個替換路由腳本

[root@stu86 lianxi]# cat cnc.txt >>tel.txt ＃文件合并
[root@stu86 lianxi]# sort -t. -k4 -n tel.txt >user.txt ＃以最后一個字段排序，并且顯示行號
[root@stu86 lianxi]# cat -n user.txt

路由腳本：
[root@stu86 lianxi]# cat cnctel.awk
#!/bin/awk -f

{
        if ($2 ~ /cnc/) {                                                      ＃如果$2w為／cnc／的話，那么就使用table1表
                system("ip ru add to "$3" ta table1 prio "$1);
        } else {
                system("ip ru add to "$3" ta table2 prio "$1);     ＃如果不是／cnc／的話執行tabla2表，$3為ip地址，$1是cat -n
        }                                                                                                                                 的行號
}
[root@stu86 lianxi]#
[root@stu86 lianxi]# ./cnctel.awk user.txt                                     ＃為user文本里面的ip集添加一個規則

責任編輯：Oo小孩兒

Linux路由腳本