網絡班第十周

1.Ubuntu系統網絡配置總結

1.1主機名

修改主機名（永久生效）

#  查看當前主機名
[Sat Jan 30 root@ubuntu 20:09~]#hostname
ubuntu
[Sat Jan 30 root@ubuntu 20:11~]#cat /etc/hostname 
ubuntu
[Sat Jan 30 root@ubuntu 20:11~]#hostnamectl 
   Static hostname: ubuntu
         Icon name: computer-vm
           Chassis: vm
        Machine ID: cc43625c00a84c8081f1477b19fac412
           Boot ID: a8d2132083a24808804ae596668a6c3e
    Virtualization: vmware
  Operating System: Ubuntu 18.04.4 LTS
            Kernel: Linux 4.15.0-130-generic
      Architecture: x86-64
[Sat Jan 30 root@ubuntu 20:11~]#uname -n
ubuntu
[Sat Jan 30 root@ubuntu 20:11~]#uname -a
Linux ubuntu 4.15.0-130-generic #134-Ubuntu SMP Tue Jan 5 20:46:26 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
[Sat Jan 30 root@ubuntu 20:11~]#

# 永久修改主機名
[Sat Jan 30 root@ubuntu 20:17~]#hostnamectl  set-hostname ubuntu1804
[Sat Jan 30 root@ubuntu 20:22~]#hostname
ubuntu1804
[Sat Jan 30 root@ubuntu 20:22~]#cat /etc/hostname 
ubuntu1804
[Sat Jan 30 root@ubuntu4 20:23~]#

# 驗證
[Sat Jan 30 root@ubuntu 20:23~]#bash
[Sat Jan 30 root@ubuntu1804 20:23~]#

1.2 網卡名稱

默認ubuntu的網卡名稱和 CentOS 7 類似，如：ens33，ens38等
修改網卡名稱為傳統命名方式：

# 修改配置文件為下面形式
[root@ubuntu1804~]#vi /etc/default/grub
GRUB_CMDLINE_LINUX="net.ifnames=0"
# 或者sed修改
[root@ubuntu1804~]# sed -i.bak '/^GRUB_CMDLINE_LINUX=/s#"$#net.ifnames=0"#'
/etc/default/grub


# 生效新的grub.cfg文件
[root@ubuntu1804~]# grub-mkconfig -o /boot/grub/grub.cfg
# 或者
[root@ubuntu1804~] update-grub
[root@ubuntu1804~]# grep net.ifnames /boot/grub/grub.cfg
linux /vmlinuz-4.15.0-96-generic root=UUID=51517b88-7e2b-4d4a-8c14-
fe1a48ba153c ro net.ifnames=0
linux /vmlinuz-4.15.0-96-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro net.ifnames=0
linux /vmlinuz-4.15.0-96-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro recovery nomodeset net.ifnames=0
linux /vmlinuz-4.15.0-76-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro net.ifnames=0
linux /vmlinuz-4.15.0-76-generic root=UUID=51517b88-7e2b-4d4a-
8c14-fe1a48ba153c ro recovery nomodeset net.ifnames=0

# 重啟生效
[root@ubuntu1804~]# reboot

1.3 Ubuntu網卡配置

1.3.1 配置自動獲取IP

范例：

[root@ubuntu1804~]# cat /etc/netplan/01-netcfg.yaml
# This file describes the network interfaces available on your system
# For more information, see netplan(5).
network:
  version: 2
  renderer: networkd
  ethernets:
    eth0:
      dhcp4: yes

修改網卡配置文件后需執行命令生效：

[root@ubuntu1804~]#netplan apply

1.3.2 配置靜態IP

范例:

[root@ubuntu1804~]#vim /etc/netplan/01-netcfg.yaml
network:
  version: 2
  renderer: networkd
  ethernets:
        eth0:
      addresses: [192.168.8.10/24,10.0.0.10/8] #或者用下面兩行,兩種格式不能混用
      - 192.168.8.10/24
      - 10.0.0.10/8
      gateway4: 192.168.8.1
      nameservers:
        search: [magedu.com, magedu.org]
        addresses: [180.76.76.76, 8.8.8.8, 1.1.1.1]

2.編寫腳本實現登陸遠程主機

2.1 交互式轉化批處理工具 expect

expect 是由Don Libes基于 Tcl（ Tool Command Language ）語言開發的，主要應用于自動化交互式操作的場景，借助 expect 處理交互的命令，可以將交互過程如：ssh登錄，ftp登錄等寫在一個腳本上，使之自動化完成。尤其適用于需要對多臺服務器執行相同操作的環境中，可以大大提高系統管理人員的工作效率

[root@centos7 ~]# yum provides expect
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
file:///mnt/cdrom/repodata/repomd.xml: [Errno 14] curl#37 - "Couldn't open file /mnt/cdrom/repodata/repomd.xml"
Trying other mirror.
expect-5.45-14.el7_1.x86_64 : A program-script interaction and testing utility
Repo        : base



expect-5.45-14.el7_1.x86_64 : A program-script interaction and testing utility
Repo        : cdrom



expect-5.45-14.el7_1.x86_64 : A program-script interaction and testing utility
Repo        : @base



[root@centos7 ~]# yum -y install expect-5.45-14.el7_1.x86_64
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
file:///mnt/cdrom/repodata/repomd.xml: [Errno 14] curl#37 - "Couldn't open file /mnt/cdrom/repodata/repomd.xml"
Trying other mirror.
Package expect-5.45-14.el7_1.x86_64 already installed and latest version
Nothing to do
[root@centos7 ~]#

expect 語法：

expect [選項] [ -c cmds ] [ [ -[f|b] ] cmdfile ] [ args ]

常見選項：
-c：從命令行執行expect腳本，默認expect是交互地執行的
-d：可以輸出輸出調試信息

expect中相關命令

spawn 啟動新的進程

expect 從進程接收字符串

send 用于向進程發送字符串

interact 允許用戶交互

exp_continue 匹配多個字符串在執行動作后加此命令

expect最常用的語法(tcl語言:模式-動作)

單一分支模式語法：

[root@centos7 ~]# expect 
expect1.1> expect "hi" {send "You said hi\n"}
hahahuhixixi
You said hi
expect1.2> exit
[root@centos7 ~]#

匹配到hi后，會輸出“you said hi”，并換行

多分支模式語法：

[root@centos7 ]#expect
expect1.1> expect "hi" { send "You said hi\n" } "hehe" { send "Hehe yourself\n"
} "bye" { send "Good bye\n" }
hehe
Hehe yourself
expect1.2> expect "hi" { send "You said hi\n" } "hehe" { send "Hehe yourself\n"
} "bye" { send "Good bye\n" }
bye
Good bye
expect1.3> expect "hi" { send "You said hi\n" } "hehe" { send "Hehe yourself\n"
} "bye" { send "Good bye\n" }
hi
You said hi
expect1.4>

匹配hi,hello,bye任意字符串時，執行相應輸出。等同如下：

expect {
"hi" { send "You said hi\n"}
"hehe" { send "Hehe yourself\n"}
"bye" { send " Good bye\n"}
}
[root@centos8 ~]#expect
expect1.1> expect {
+> "hi" { send "You said hi\n"}
+> "hehe" { send "Hehe yourself\n"}
+> "bye" { send " Good bye\n"}
+> }
bye
Good bye
expect1.2>

范例1

#!/usr/bin/expect
spawn scp /etc/fstab 10.0.0.7:/data
expect {
    "yes/no" { send "yes\n";exp_continue }
    "password" { send "magedu\n" }
}
expect eof

范例2

#!/usr/bin/expect
spawn ssh 10.0.0.7
expect {
    "yes/no" { send "yes\n";exp_continue }
    "password" { send "magedu\n" }
}
interact

范例3：expect 變量

#!/usr/bin/expect
set ip 10.0.0.7
set user root
set password magedu
set timeout 10
spawn ssh $user@$ip
expect {
"yes/no" { send "yes\n";exp_continue }
"password" { send "$password\n" }
}
interact

范例4：expect 位置參數

[root@centos8 scripts]#cat expect4
#!/usr/bin/expect
set ip [lindex $argv 0]
set user [lindex $argv 1]
set password [lindex $argv 2]
spawn ssh $user@$ip
expect {
    "yes/no" { send "yes\n";exp_continue }
    "password" { send "$password\n" }
}
interact
[root@centos8 scripts]#./expect4 10.0.0.7 root magedu
spawn ssh root@10.0.0.7
root@10.0.0.7's password:
Last login: Wed Apr 29 15:34:14 2020 from 10.0.0.8
[root@centos7 ~]#

范例5：expect 執行多個命令

#!/usr/bin/expect
set ip [lindex $argv 0]
set user [lindex $argv 1]
set password [lindex $argv 2]
set timeout 10
spawn ssh $user@$ip
expect {
      "yes/no" { send "yes\n";exp_continue }
      "password" { send "$password\n" }
}
expect "]#" { send "useradd haha\n" }
expect "]#" { send "echo magedu |passwd --stdin haha\n" }
send "exit\n"
expect eof
#./ssh4.exp 10.0.0.7 root magedu

范例6：shell腳本調用expect

#!/bin/bash
ip=$1
user=$2
password=$3
expect <<EOF
set timeout 20
spawn ssh $user@$ip
expect {
      "yes/no" { send "yes\n";exp_continue }
      "password" { send "$password\n" }
}
expect "]#" { send "useradd hehe\n" }
expect "]#" { send "echo magedu |passwd --stdin hehe\n" }
expect "]#" { send "exit\n" }
expect eof
EOF
#./ssh5.sh 192.168.8.10 root magedu

范例7: shell腳本利用循環調用expect在CentOS和Ubuntu上批量創建用戶

#!/bin/bash

NET=10.0.0
user=root
password=magedu
for ID in 6 7 111;do
ip=$NET.$ID
expect <<EOF
set timeout 20
spawn ssh $user@$ip
expect {
    "yes/no" { send "yes\n";exp_continue }
    "password" { send "$password\n" }
}
expect "#" { send "useradd test\n" }
expect "#" { send "exit\n" }
expect eof
EOF
done

練習1：expect腳本實現登陸遠程主機

[root@centos7 ~]# cd /data/scripts
[root@centos7 scripts]# ls
[root@centos7 scripts]# vim expect1
[root@centos7 scripts]# cat  expect1
[root@centos7 scripts]# cat expect1
#!/usr/bin/expect
set  ip        [lindex $argv 0]
set  user      [lindex $argv 1]
set  password  [lindex $argv 2]
spawn ssh $user@$ip
expect {
        "yes/no" { send "yes\n";exp_continue }
        "password" { send "$password\n" }
}
interact
[root@centos7 scripts]# chmod +x expect1 
[root@centos7 scripts]# ./expect1  10.0.0.88  root  666666
spawn ssh root@10.0.0.88
root@10.0.0.88's password: 
Web console: https://centos8:9090/ or https://10.0.0.88:9090/

Last login: Sun Jan 31 05:29:54 2021 from 10.0.0.10
[Sun Jan 31 root@centos8 05:30~]#exit
logout
Connection to 10.0.0.88 closed.
[root@centos7 scripts]#

練習2：shell腳本實現登陸遠程主機

[root@centos7 scripts]# ls
expect1
[root@centos7 scripts]# ll
total 4
-rwxr-xr-x 1 root root 231 Jan 31 05:23 expect1
[root@centos7 scripts]# vim ssh.sh
[root@centos7 scripts]# chmod +x  ssh.sh
[root@centos7 scripts]# ll
total 8
-rwxr-xr-x 1 root root 231 Jan 31 05:23 expect1
-rwxr-xr-x 1 root root 726 Jan 31 05:39 ssh.sh
[root@centos7 scripts]# cat ssh.sh 
[root@centos7 scripts]# vim ssh.sh
[root@centos7 scripts]# cat ssh.sh 
#!/bin/bash

ip=$1
user=$2
password=$3
expect <<EOF
spawn ssh $user@$ip
expect {
    "yes/no" { send "yes\n";exp_continue }
    "password" { send "$password\n" }
}
expect "]#" { send "exit\n" }
expect eof
EOF
[root@centos7 scripts]# ./ssh.sh 10.0.0.88 root 666666
spawn ssh root@10.0.0.88
root@10.0.0.88's password: 
Web console: https://centos8:9090/ or https://10.0.0.88:9090/

Last login: Sun Jan 31 06:07:59 2021 from 10.0.0.10
[Sun Jan 31 root@centos8 06:25~]#exit
logout
Connection to 10.0.0.88 closed.
[root@centos7 scripts]#

備注：在第二個EOF的時候，后面不要有空格，否則報錯：

　　　　invalid command name "EOF"

　　　　while executing

　　　　　　"EOF "

　　　把后面的空格去掉即可

3.數組array

3.1 數組介紹

變量：存儲單個元素的內存空間

數組：存儲多個元素的連續的內存空間，相當于多個變量的集合

數組名和索引

索引的編號從0開始，屬于數值索引

索引可支持使用自定義的格式，而不僅是數值格式，即為關聯索引，bash4.0版本之后開始支持

bash的數組支持稀疏格式（索引不連續）

3.2 聲明數組

#普通數組可以不事先聲明,直接使用
declare -a ARRAY_NAME
#關聯數組必須先聲明,再使用
declare -A ARRAY_NAME

注意：兩者不可相互轉換

3.3 數組賦值

數組元素的賦值
(1) 一次只賦值一個元素

ARRAY_NAME[INDEX]=VALUE

weekdays[0]="Sunday"
weekdays[4]="Thursday"

(2) 一次賦值全部元素

ARRAY_NAME=("VAL1" "VAL2" "VAL3" ...)

title=("ceo" "coo" "cto")
num=({0..10})
alpha=({a..g})
file=( *.sh )

(3) 只賦值特定元素

ARRAY_NAME=([0]="VAL1" [3]="VAL2" ...)

(4) 交互式數組值對賦值

read -a ARRAY

3.4 顯示所有數組

顯示所有數組：

declare -a

3.5 引用數組

引用數組元素

${ARRAY_NAME[INDEX]}
#如果省略[INDEX]表示引用下標為0的元素

[root@centos8 ~]#declare -a title=([0]="ceo" [1]="coo" [2]="cto")
[root@centos8 ~]#echo ${title[1]}
coo
[root@centos8 ~]#echo ${title}
ceo
[root@centos8 ~]#echo ${title[2]}
cto
[root@centos8 ~]#

引用數組所有元素

${ARRAY_NAME[*]}
${ARRAY_NAME[@]}

[root@centos8 ~]#echo ${title[@]}
ceo coo cto
[root@centos8 ~]#echo ${title[*]}
ceo coo cto

數組的長度，即數組中元素的個數

${#ARRAY_NAME[*]}
${#ARRAY_NAME[@]}

[root@centos8 ~]#echo ${#title[*]}
3

3.6 刪除數組

刪除數組中的某元素，會導致稀疏格式

unset ARRAY[INDEX]

[root@centos8 ~]#echo ${title[*]}
ceo coo cto
[root@centos8 ~]#unset title[1]
[root@centos8 ~]#echo ${title[*]}
ceo cto

刪除整個數組

unset ARRAY

3.7 數組數據處理

數組切片：

${ARRAY[@]:offset:number}
offset #要跳過的元素個數
number #要取出的元素個數
#取偏移量之后的所有元素
{ARRAY[@]:offset}

[root@centos8 ~]#num=({0..10})
[root@centos8 ~]#echo ${num[*]:2:3}
2 3 4
[root@centos8 ~]#echo ${num[*]:6}
6 7 8 9 10

向數組中追加元素：

ARRAY[${#ARRAY[*]}]=value
ARRAY[${#ARRAY[@]}]=value

[root@centos8 ~]#num[${#num[@]}]=11
[root@centos8 ~]#echo ${#num[@]}
12
[root@centos8 ~]#echo ${num[@]}
0 1 2 3 4 5 6 7 8 9 10 11

3.8 關聯數組

declare -A ARRAY_NAME
ARRAY_NAME=([idx_name1]='val1' [idx_name2]='val2‘...)

注意：關聯數組必須先聲明再調用

[root@centos8 ~]#name[ceo]=mage
[root@centos8 ~]#name[cto]=wang
[root@centos8 ~]#name[coo]=zhang
[root@centos8 ~]#echo ${name[ceo]}
zhang
[root@centos8 ~]#echo ${name[cto]}
zhang
[root@centos8 ~]#echo ${name[coo]}
zhang
[root@centos8 ~]#echo ${name}
zhang
[root@centos8 ~]#declare -A name
-bash: declare: name: cannot convert indexed to associative array
[root@centos8 ~]#unset name
[root@centos8 ~]#declare -A name
[root@centos8 ~]#name[ceo]=mage
[root@centos8 ~]#name[cto]=wang
[root@centos8 ~]#name[coo]=zhang
[root@centos8 ~]#echo ${name[coo]}
zhang
[root@centos8 ~]#echo ${name[ceo]}
mage
[root@centos8 ~]#echo ${name[cto]}
wang
[root@centos8 ~]#echo ${name[*]}
mage wang zhang

[root@centos8 ~]#declare -A student
[root@centos8 ~]#student[name1]=lijun
[root@centos8 ~]#student[name2]=ziqing
[root@centos8 ~]#student[age1]=18
[root@centos8 ~]#student[age2]=16
[root@centos8 ~]#student[gender1]=m
[root@centos8 ~]#student[city1]=nanjing
[root@centos8 ~]#student[gender2]=f
[root@centos8 ~]#student[city2]=anhui
[root@centos8 ~]#student[gender2]=m
[root@centos8 ~]#student[name50]=alice
[root@centos8 ~]#student[name3]=tom
[root@centos8 ~]#for i in {1..50};do echo student[name$i]=${student[name$i]};
done

練習3：

生成10個隨機數保存于數組中，并找出其最大值和最小值

[root@centos7 ~]# cd /data/scripts/
[root@centos7 scripts]# ls
expect1  ssh.sh
[root@centos7 scripts]# vim min_max.sh
[root@centos7 scripts]# cat min_max.sh
#!/bin/bash

declare -i min max
declare -a nums
for ((i=0;i<10;i++));do
nums[$i]=$RANDOM
    [ $i -eq 0 ] && min=${nums[0]} && max=${nums[0]}&& continue
    [ ${nums[$i]} -gt $max ] && max=${nums[$i]}
    [ ${nums[$i]} -lt $min ] && min=${nums[$i]}
done
echo "All numbers are ${nums[*]}"
echo Max is $max
echo Min is $min
[root@centos7 scripts]# chmod +x min_max.sh 
[root@centos7 scripts]# ./min_max.sh 
All numbers are 5555 22926 3870 323 28707 7512 2245 23751 19875 3346
Max is 28707
Min is 323
[root@centos7 scripts]# ./min_max.sh 
All numbers are 20910 6826 5802 2442 225 22828 25655 27198 11012 8001
Max is 27198
Min is 225
[root@centos7 scripts]#

練習4：

輸入若干個數值存入數組中，采用冒泡算法進行升序或降序排序

# 降序排列
[root@centos7 scripts]# vim bubble_array.sh
[root@centos7 scripts]# cat bubble_array.sh
#!/bin/bash

declare -a number
read -p "Please enter the number of generated random numbers:" num
for (( i=0; i<$num; i++ ));do
  number[$i]=$RANDOM
done
echo "before sort:"
echo ${number[@]}

declare -i n=$num
for (( i=0; i<n-1; i++ ));do
  for (( j=0; j<n-1-i; j++ ));do
    let next=$j+1
    if (( ${number[$j]} < ${number[$next]} ));then
      tmp=${number[$next]}
      number[$next]=${number[$j]}
      number[$j]=$tmp
    fi
  done
done
echo "after sort:"
echo ${number[*]}
echo "the max integer is ${number[0]},the min integer is ${number[$(( n-1 ))]}"
[root@centos7 scripts]# chmod +x bubble_array.sh 
[root@centos7 scripts]# ./bubble_array.sh 
Please enter the number of generated random numbers:5
before sort:
6205 32176 17353 17808 428
after sort:
32176 17808 17353 6205 428
the max integer is 32176,the min integer is 428
[root@centos7 scripts]# ./bubble_array.sh 
Please enter the number of generated random numbers:7
before sort:
32755 24283 6732 1471 30819 25775 9916
after sort:
32755 30819 25775 24283 9916 6732 1471
the max integer is 32755,the min integer is 1471
[root@centos7 scripts]#


# 升序排列
[root@centos7 scripts]# vim bubble_array2.sh
[root@centos7 scripts]# cat bubble_array2.sh
#!/bin/bash

read -p "Please enter the number of generated random numbers:" num
declare -a number
for (( i=0; i<$num; i++ ));do
  number[$i]=$RANDOM
done
echo "before sort:"
echo ${number[@]}

declare -i n=$num
for (( i=0; i<n-1; i++ ));do
  for (( j=0; j<n-1-i; j++ ));do
    let next=$j+1
    if (( ${number[$j]} > ${number[$next]} ));then
      tmp=${number[$next]}
      number[$next]=${number[$j]}
      number[$j]=$tmp
    fi
  done
done
echo "after sort:"
echo ${number[*]}
echo "the max integer is ${number[$(( n-1 ))]},the min integer is  ${number[0]}"
[root@centos7 scripts]# chmod +x bubble_array2.sh 
[root@centos7 scripts]# ./bubble_array2.sh 
Please enter the number of generated random numbers:5
before sort:
10717 32617 27697 11975 8984
after sort:
8984 10717 11975 27697 32617
the max integer is 32617,the min integer is  8984
[root@centos7 scripts]# ./bubble_array2.sh 
Please enter the number of generated random numbers:9
before sort:
8736 6940 25929 23407 3386 31846 12175 32605 29410
after sort:
3386 6940 8736 12175 23407 25929 29410 31846 32605
the max integer is 32605,the min integer is  3386
[root@centos7 scripts]#

posted on 2021-01-31 17:32 ~~十面埋伏~~ 閱讀(112) 評論(1) 收藏舉報

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