Linux System Engineer Technology (Engineer)-------fifth day

Two virtual machines, all to be detected

1. is yum available

2. Firewall default zone modified to trusted

3. Whether the IP address is configured

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Second, ordinary users (must restore the environment)

??

??? Client access to the service-side Nfs-server service for ordinary users

The server will determine the permissions of the local user with the same UID as the client.

? ? LDAP: Network user, provide user name

? ? Kerberos: Password authentication, implementation of "One-time password authentication, multiple free login" pass mechanism

1. Two virtual machines run scripts to join LDAP and Kerberos

??

? # Lab NFSKRB5 Setup

2. The server modifies the configuration file to create a read-write share

[Email protected] ~]# mkdir/test

[Email protected] ~]# Vim/etc/exports

??/test? * (rw,sec=krb5p)

3. Server-side deployment of encrypted keys

# wget Http://172.25.254.254/pub/keytabs/server0.keytab?-o/etc/krb5.keytab

# ls?/etc/krb5.keytab

4. Service end multiplicity from Nfs-server and nfs-secure-server?

# systemctl restart? nfs-server? nfs-secure-server?

5. Service side guarantee Ldapuser0 user has Write permission, set local permissions

[Email protected] ~]# setfacl-m u:ldapuser0:rwx/test

[Email protected] ~]# getfacl/test

6. Client Access and Mount sharing

[Email protected] ~]# showmount-e 172.25.0.11

[Email protected] ~]# Mkdir/mnt/nfs

[Email protected] ~]# Vim/etc/fstab?

? 172.25.0.11:/test/mnt/nfs? NFS _netdev,sec=krb5p? 0? 0

7. Client deployment key file, restart related services

# wget Http://172.25.254.254/pub/keytabs/desktop0.keytab?-o/etc/krb5.keytab

# Systemctl Restart NFS Nfs-secure

8. Client-side verification mount, write (must be in SSH mode, SU without Kerberos authentication)

[Email protected] ~]# mount-a

[Email protected] ~]# df-h

[[email protected] ~]# ssh [email protected]

[Email protected] ~]$ cd/mnt/nfs/

[[email protected] nfs]$ Touch 1.txt

[[email protected] nfs]$ ls

1.txt

[[Email protected] nfs]$ exit

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? Shell Script

???? Script: Can execute a file, after running can implement some function (command stack, non-interactive)

Standardize the general composition of shell scripts

? #! Environmental Statement (Sha-bang)

? # comment Text

? Executable code

I. Writing the first script program

[Email protected] ~]# vim/root/1.sh?

? #!/bin/bash

? echo Hello World

? hostname

? cat?/etc/redhat-release

? ifconfig | Head-2? | Tail-1

[Email protected] ~]#/root/1.sh

Second, write for SERVER0 automatically build Yum script

[Email protected] ~]# vim/root/yum.sh?

? #!/bin/bash

? da

[Email protected] ~]# chmod +x/root/yum.sh

[Email protected] ~]#/root/yum.sh

Pipeline Delivery

? Use | Pipeline operation

– The standard output from the previous command is given to the latter command to process

Third, redirect output

? ? Collect only the correct output from the previous command

? ? 2>: Collect only the error output from the previous command

? ? &>: Collect errors and correct output from the previous command

[Email protected] ~]# echo 123 >/opt/1.txt

[Email protected] ~]# Cat/opt/1.txt

[Email protected] ~]# cat/opt/1.txt/etc/

[Email protected] ~]# cat/opt/1.txt/etc/>/opt/a.txt

[Email protected] ~]# Cat/opt/a.txt

[Email protected] ~]# cat/opt/1.txt/etc/2>/opt/a.txt

[Email protected] ~]# Cat/opt/a.txt

[Email protected] ~]# cat/opt/1.txt/etc/&>/opt/a.txt

[Email protected] ~]# Cat/opt/a.txt

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Iii. writing a script to create a user and set a password

/dev/null? #Linux黑洞设备, designed to collect not output results

[Email protected] ~]# vim/root/user.sh

? #!/bin/bash

? useradd test06 &>/dev/null

? Echo Test06 created successfully

? Echo 123 | passwd--stdin test06 &>/dev/null

The Echo test06 password setting was successful.

[Email protected] ~]# chmod +x/root/user.sh

[Email protected] ~]#/root/user.sh

??

?? variable: To increase the ability of the script to apply the environment, increase the flexibility of the script, convenient. -----------Introducing Variables

The variable: The container, with the invariant name, stores the changed value

? ? ? Variable name = changed value

? Use variable:?? $ variable Name

In order to reduce the difficulty of script use, you can create interactive

? Read? : Interaction can be generated to assign the contents of the keyboard input to the variable

[Email protected] ~]# vim/root/user.sh

? #!/bin/bash

? read-P? ' Please enter the user you want to create: '? User

? read-P? ' Please enter the password you want to set: '? Pass

Useradd? $user?&>/dev/null

? Echo $user created successfully

? echo $pass | passwd--stdin $user &>/dev/null

The echo $user password is set successfully.

[Email protected] ~]#/root/user.sh

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What is a variable

? Values that are stored as immutable names that may vary

– Variable name = variable Value

– Easy to reuse a value with a fixed name

– Improved adaptability to mission requirements and operational environment changes

? Considerations when setting a variable

– If the specified variable name already exists, it is equivalent to re-assigning a value to this variable

– Don't have spaces on both sides of the equals sign

– Variable names are made up of letters/numbers/underscores, case-sensitive

– Variable names cannot start with a number, do not use keywords and special characters

? Basic format

– Reference variable Value: $ variable Name

– View variable values: Echo $ variable name, echo ${variable name}

? Types of variables

Positional variables

? Command-line arguments (non-interactive pass-through values) that are provided when the script is executed

[Email protected] ~]# vim?/root/2.sh

? #!/bin/bash

? Echo $

? Echo $

? Echo $

? Echo ${10}

? Echo ${11}

#/root/2.sh haha benniu? xixi? hehe? Lele? DC? TC? Dz? TZ 100 200

[Email protected] ~]# vim/root/3.sh

? #!/bin/bash

? Cat-n? | ? head-$2?

[Email protected] ~]#/root/3.sh/etc/passwd? 2

[Email protected] ~]#/root/3.sh/etc/passwd? 3

? pre-defined variables

? ? The execution information used to save the script

– Use these variables directly

– You cannot assign values directly to these variables

? $#? The number of position variables that have been loaded

$*? Values for all positional variables

$?? status value after program exit, 0 indicates normal, other value exception

[Email protected] ~]# vim/root/2.sh?

? #!/bin/bash

? Echo $

? Echo $

? Echo $

? Echo ${10}

? Echo ${11}

? Echo $#

? Echo $*

[Email protected] ~]#/root/2.sh 1? 2 3 4 5 6 7 8 9 10 11

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Operation?

??

[[email protected] ~]# expr 10/3

[[email protected] ~]# Expr 10 \* 3

[[email protected] ~]# Expr 1 + 2

[[email protected] ~]# expr 3-1

[Email protected] ~]# expr 3?? #取余数 operation

? $ (): The output of the command, as a parameter

[[Email protected] opt]# Date

[Email protected] opt]# date +%f

[Email protected] opt]# cd/opt

[Email protected] opt]# mkdir? $ (Date +%f)

[[email protected] opt]# ls

[Email protected] opt]# mkdir? mydir-$ (Date +%f)

[[email protected] opt]# ls

[Email protected] opt]# mkdir? mariadb-$ (Date +%f)

[[email protected] opt]# ls

[Email protected] opt]# mkdir? $ (hostname)-$ (date +%f)

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Common Test Options

? Check file status

-e: Document exists as true

-D: Document exists and is directory-True

-F: Document exists and is file-true

-r: Document exists with Read permission true

-W: Document exists with Write permission true

-X: Document exists with Execute permission true

? Compare integer size (with E equals two words, g for greater than, l for less)---------only for numbers

-GT: Greater Than

-ge: greater than or equal to

-eq: Equals

-ne: Not equal to

-LT: Less than

-le: Less than or equal to

? string alignment

= =: Equal

! =: Not Equal

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If [condition test]; Then

??? command sequence XX

? Else

??? command sequence YY

? fi

[Email protected]/]# vim?/root/5.sh

? #!/bin/bash

? If? [$1-eq $];then

?? Echo Hello

? Else

?? Echo Hi

? fi

[Email protected]/]#/root/5.sh? 1 1?

[Email protected]/]#/root/5.sh? 1 2

?? Please write a script:

? ? ? The user enters an IP address (read) to determine if it can communicate with the IP address.

Can you output "IP OK" in general? Otherwise the output "IP no"

[Email protected]/]# vim?/root/6.sh

?? #!/bin/bash

?? read-P? ' Please enter an IP address: '?? IP

?. ping?-C 2? $ip?&>/dev/null

??? if [$?-eq 0];then

? ? ? ? ? echo? ${ip} OK

? ? ? Else

? ? ? ? ? echo? ${ip} no?

???? Fi?

[email protected]/]#? /root/6.sh

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If [condition test 1]; Then

? ? ? Command sequence XX

elif [condition Test 2]; Then

? ? ? Command Sequence yy

? Else

? ? ? Command Sequence ZZ

? fi

??

? ? ?

? ? The result is greater than or equal to 90. Good

? is greater than or equal to 80??????????

? is greater than or equal to 70??

? greater than or equal to 60? Do you still have to work?

Less than 60????? In the cattle of Chopin, also can not play out elder brother Sadness

[Email protected] ~]# vim/root/8.sh

#!/bin/bash

? read-p? ' Please enter your score: '?? Num

If [$num-gt];then

??? Echo's wrong result

? elif [$num-lt 0];then

??? Echo's wrong result

? elif [$num-ge];then

??? Echo Excellent

? elif [$num-ge];then

??? Echo Good

? elif [$num-ge];then

??? Echo passed

? elif [$num-ge];then

??? Echo still needs to work

? Else?

? ? echo in the Ox Chopin, also can not play the elder brother Sadness

Fi

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Create a/root/foo.sh script on Server0

1) When running/root/foo.sh Redhat, the output is Fedora

2) When running/root/foo.sh fedora, output is Redhat

3) when no parameters or parameters are not redhat or

When fedora, its error output produces the following information:?

? /root/foo.sh? Redhat|fedora

? ? ?‘ ': Put all the special characters, as normal text characters output

[Email protected] ~]# vim?/root/foo.sh

? #!/bin/bash

? if [? $ = = Redhat?]; Then

?? Echo Fedora

? elif [?] = =? Fedora?]; Then

?? echo? redhat

? Else

"Echo?" /root/foo.sh? Redhat|fedora '

? fi

[Email protected] ~]#/root/foo.sh Redhat

[Email protected] ~]#/root/foo.sh Fedora

[Email protected] ~]#/root/foo.sh haha

? #!/bin/bash

? If [$#-eq 0];then

?? Echo '/root/foo.sh? Redhat|fedora '

? elif [= = Redhat];then

?? Echo Fedora

? elif [= = = Fedora];then

?? Echo Redhat

? Else

?? Echo '/root/foo.sh? Redhat|fedora '

? fi

? ? ??

? ? ? ?" ": You can Change" no "to" null "

? ? ? ?" "to make = = They are two equal, in the middle must have something to add, otherwise" "and = = is not equal, column such as" $ "= = Redhat?

? #!/bin/bash

? If [?] $ "= = Redhat];then

?? Echo Fedora

? elif ["$" = = Fedora];then

?? Echo Redhat

? Else

?? Echo '/root/foo.sh Redhat|fedora '? >&2? #将正确输出变成错误

The Exit 2????????????????????????????? #脚本退出返回值

? fi

Add: Echo '/root/foo.sh redhat|fedora '? >&2-----was wrong with what was in the Echo ', but Linux doesn't know that the output is wrong, so you want to turn the error output back on > &2, so you can output the wrong information. Then add a return value, exit 1, so you know it's wrong or correct

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? For loop structure

? Loop structure: The repeated execution of the statement, loop to execute

? For variable name in? Value List

? Do

? ? ? ? Command sequence

? Done

[Email protected]/]# vim?/root/for.sh

? #!/bin/bash

? For a in 1 2 3 4 5

? Do

? ? Useradd nsd$a

? ? Echo Nsd$a created successfully

? Done

[Email protected]/]# vim?/root/for02.sh

? #!/bin/bash

? For a in 1 2 3 4 5

? Do

? ? ? echo Hello

? Done

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Case 5: Write a bulk Add user script

Create a/root/batchusers script on Server0??????

1) This script requires a user name list file as a parameter

2) If no parameters are provided, should this script give a hint?

? ? ? ? Usage:/root/batchusers, exit and return the corresponding value

3) If a nonexistent file is provided, this script should give a

Show Input file not found, exit and return the corresponding value

4) New User login Shell is/bin/false, no need to set password

5) User list test file:

Http://classroom/pub/materials/userlist

?

# wgethttp://classroom/pub/materials/userlist?

[Email protected]/]# vim?/root/batchusers

? #!/bin/bash

? If [$#-eq 0];then

? ? Echo ' Usage:/root/batchusers ' >&2

? ? Exit 1

? fi

? if [!-e $];then

? ? Echo ' Input file not found ' >&2

? ? Exit 2

? fi

? for. A? in $ (cat $)

? do

? ? Useradd-s/bin/false $a

? ? Echo $a created successfully

? done

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? #!/bin/bash

? If [$#-eq 0];then

? ? Echo ' Usage:/root/batchusers ' >&2

? ? Exit 1

? fi

? If [-E $];then

? ? For. A? in $ (cat $)

??? do

? ? Useradd-s/bin/false $a

? ? Echo $a created successfully

??? done

? Else

? ? Echo ' Input file not found ' >&2

? ? Exit 2

? fi

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? ? ? ? ?

?

Linux System Engineer Technology (Engineer)-------fifth day