【故障集合】Linux必备故障及原因50个老男孩Linux

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2020年12月3日 15:50

老男孩Linux运维培训班学习中，Linux故障集合都有哪些？老男孩Linux培训课程，从0基础到云计算架构系列教学，全程面授实战，帮助Linux学习者入门Linux运维课程

此文档送给刚刚学习Linux的各位小伙伴

零.目录

一. 文件和目录类

File exist 文件已经存在

No such file or directory 没有这个文件或目录(这个东西不存在)

command not found 命令找不到(没有这个命令)

invalid option 无效的参数(不可用的参数)

overwrite 覆盖

remove regular empty file 是否删除普通文件(空的)?

is a directory xxx是一个目录

descend into directory 是否进入目录

Invalid level 无效的层数,层数必须大于0

Can't open file for writing 无法打开这个文件

No write since last change

xx column window is too narrow 窗口只有xx列太窄了无法完全显示

xxx not a directory 不是一个目录

查看压缩包的时候报错

You have mail in /var/spool/mail/root

permission denied

Warning: Changing a readonly file

'readonly' option is set (add ! to override)

cp: omitting directory ‘/oldboy/’ unexpected end of file 或 Unexpected EOF in archive

二. 网络连接类

远程连接错误 Connection Failed 连接失败

yum安装软件故障提示 Could not resolve host无法解析主机

yum安装软件提示:Nothing to do (没事做)

没有找到叫treea的软件包

Name or service not known 域名无法识别(无法上网）

三. 修改系统基础配置类

重启网卡报错 device not present

修改主机名过程中,命令行中主机名没有变化

hostname命令修改主机名（临时重启服务器之后失效）

命令行中的主机名部分没有改变？

四. 用户相关错误

user 'oldboy' already exists

no such user

Only root can do that.

Only root can specify a user name.

Creating mailbox file: File exists

warning: the home directory already exists.

/etc/sudoers: syntax error near line 105 <<<

五.脚本及定时任务

一. 文件和目录类

1. File exist 文件已经存在

[root@oldboyedu59 ~]# mkdir   /data   /lidao  
[root@oldboyedu59 ~]# mkdir   /data   /lidao  
mkdir: cannot create directory ‘/data’: File exists
mkdir: cannot create directory ‘/lidao’: File exists

mkdir: cannot create directory ‘/lidao’: File exists 无法创建目录因为这个目录已经存在

2. No such file or directory 没有这个文件或目录(这个东西不存在)

没有这个目录:文件或路径书写错误

[root@oldboyedu59 ~]# mkdir  /oldboy
[root@oldboyedu59 ~]# cd oldboy
-bash: cd: oldboy: No such file or directory

mkdir命令本身问题:mkdir 命令默认只能创建1层目录创建多层报错 -p解决

[root@oldboyedu59 ~]# mkdir  /data/oldboy/lidao/
mkdir: cannot create directory ‘/data/oldboy/lidao/’: No such file or directory

touch命令只能创建文件,目录不存在则会报错解决:先创建目录,再创建文件

[root@oldboyedu59 ~]# ls /oldboy/
oldboy.txt
[root@oldboyedu59 ~]# touch /oldboy/lidao/alex/oldboy.txt
touch: cannot touch ‘/oldboy/lidao/alex/oldboy.txt’: No such file or directory

排错思路: 1.ls命令检查对应的目录是否存在? 2.目录不存在先创建目录在创建文件/

find命令与|xargs ll 错误 |xargs后面不支持别名

[root@kangxu ~]# find /oldboy  -name  "*.txt"  -type f |xargs ll
xargs: ll: No such file or directory

3. command not found 命令找不到(没有这个命令)

[root@oldboyedu59 ~]# mkdiy
-bash: mkdiy: command not found

1.书写错误 2.没有安装

4. invalid option 无效的参数(不可用的参数)

 [root@oldboyedu59 ~]# touch -p /oldboy/oldboy.txt
touch: invalid option -- 'p'
Try 'touch --help' for more information.

5. overwrite 覆盖

cp复制如果已经存在这个文件会提示是否覆盖

[root@oldboyedu59 ~]# cp  /oldboy/oldboy.txt   /tmp/
cp: overwrite ‘/tmp/oldboy.txt’?

6.remove regular empty file 是否删除普通文件(空的)？

[root@oldboyedu59 ~]# rm   /oldboy/oldboy.txt
rm: remove regular empty file ‘/oldboy/oldboy.txt’?

7. is a directory xxx是一个目录

rm默认无法删除目录解决:加上-r 或-rf

[root@oldboyedu59 ~]# rm /data/
rm: cannot remove ‘/data/’: Is a directory

vi命令中使用vi编辑目录也会报错

"/oldboy"
E502: "/oldboy" is a directory
Press ENTER or type command to continue

8. descend into directory 是否进入目录

[root@oldboyedu59 ~]# rm -r /data/
rm: descend into directory ‘/data/’? y
rm: remove regular empty file ‘/data/oldboy01.txt’? n
rm: remove regular empty file ‘/data/oldboy02.txt’? n
rm: remove regular empty file ‘/data/oldboy03.txt’? n
rm: remove regular empty file ‘/data/oldboy04.txt’? n
rm: remove regular empty file ‘/data/oldboy05.txt’? n
rm: remove regular empty file ‘/data/oldboy06.txt’? n
rm: remove regular empty file ‘/data/oldboy07.txt’? n
rm: remove regular empty file ‘/data/oldboy08.txt’? n
rm: remove regular empty file ‘/data/oldboy09.txt’? n
rm: remove regular empty file ‘/data/oldboy10.txt’? n
rm: remove directory ‘/data/’? n

9. Invalid level 无效的层数,层数必须大于0

注意参数位置

[root@oldboyedu59 ~]# tree  -L -F 2 / 
tree: Invalid level, must be greater than 0.

10. Can't open file for writing 无法打开这个文件

vi中如果目录不存在就会提示

"/oldbyo/oldboy.txt"
"/oldbyo/oldboy.txt" E212: Can't open file for writing
Press ENTER or type command to continue

如果你对这个文件没有权限也会提示

11.No write since last change

E37: No write since last change (add ! to override)
     粘包赖(你修改了内容就无法使用:q退出 需要使用:q!

12. xx column window is too narrow 窗口只有xx列太窄了无法完全显示

这是w的坑空间太小施展不开.

[root@oldboyedu60-lnb ~]# w
w: 39 column window is too narrow

13. xxx not a directory 不是一个目录

背景:创建文件的时候多了一个空格

[root@ssdz ~]# touch /oldboy /oldboy.txt  #此处要创建/oldboy/oldboy.txt 多个个空格 创建了2个文件 /oldboy和/oldboy.txt 
[root@ssdz ~]# ls -l /oldboy/         #系统认为oldboy是个目录 所以报错
ls: cannot access /oldboy/: Not a directory
[root@ssdz ~]# touch /oldboy/oldboy.txt
touch: cannot touch ‘/oldboy/oldboy.txt’: Not a directory
[root@ssdz ~]# ls -l /oldboy
-rw-r--r--. 1 root root 0 Apr  9 15:23 /oldboy

14.查看压缩包的时候报错

注意是否有特殊中文符号导致的。

[root@oldboy59 tmp]# tar ztf /tmp/etc.tar.gz
tar (child): \200\202\200\202\200\202\200\202/tmp/etc.tar.gz: Cannot open: No such file or directory
tar (child): Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error is not recoverable: exiting now

15. You have mail in /var/spool/mail/root

你在这个文件/var/spool/mail/root 中有一个新邮件

16. permission denied

权限拒绝

17. W10: Warning: Changing a readonly file

使用vim的时候显示的表示：正在修改只读文件解决:

1.查看对文件是否有rw权限 2.如果是root用户可以修改后强制保存退出(:wq!)

18.no properly formatted MD5 checksum lines found

在使用md5sum -c (检查的时候） md5指纹信息文件中，格式不对第1列是md5 信息第2列文件名解决:

查看MD5文件内容是否正确检查的命令是否正确 md5sum -c oldboy.md5

md5sum: /oldboy/mtime/access_2019-04-01.txt: no properly formatted MD5 checksum lines found

19. E45: 'readonly' option is set (add ! to override)

通过vi/vim 编辑文件保存的时候(:wq) 提示这个文件只读，:wq! 强制保存退出

20. cp: omitting directory ‘/oldboy/’

忽略这个目录 cp默认无法复制目录

[root@oldboyedu64-lnb ~]# cp /oldboy/  /tmp/
cp: omitting directory ‘/oldboy/’
[root@oldboyedu64-lnb ~]# ls -l /tmp/
total 8
-rwx------. 1 root root 836 Jun 30 17:36 ks-script-gWLqG0
-rw-r--r--. 1 root root 400 Jul  7 14:51 oldboy.txt
drwx------. 2 root root   6 Jun 30 17:42 vmware-root_6749-3879179984
-rw-------. 1 root root   0 Jun 30 17:27 yum.log

21. Unexpected EOF in archive

未知的压缩文件结尾主要原因是tar压缩包损坏重新下载

[root@web02 tools]# tar xf nginx-1.16.0.tar.gz 

gzip: stdin: unexpected end of file
tar: Unexpected EOF in archive
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now

二. 网络连接类

1. 远程连接错误 Connection Failed 连接失败

使用Xshell远程连接失败提示,检查端口是否开启或正确

[c:\~]$ 

Connecting to 10.0.0.200:233...
Could not connect to '10.0.0.200' (port 233): Connection failed.

Type `help' to learn how to use Xshell prompt.

使用telnet测试端口是否打开

[c:\~]$ telnet 10.0.0.200 233 

Connecting to 10.0.0.200:233...
Could not connect to '10.0.0.200' (port 233): Connection failed.   #233端口没有开启

Type `help' to learn how to use Xshell prompt.

端口开启

[c:\~]$ telnet 10.0.0.200 22
Connecting to 10.0.0.200:22...
Connection established.            #端口开启
To escape to local shell, press 'Ctrl+Alt+]'.
SSH-2.0-OpenSSH_7.4

Protocol mismatch.

Connection closed by foreign host.

Disconnected from remote host(10.0.0.200:22) at 12:22:54.

Type `help' to learn how to use Xshell prompt.
[c:\~]$

2. yum安装软件故障提示 Could not resolve host无法解析主机

Could not resolve host无法解析主机主要是系统能否上网和DNS问题.

http://mirrors.tuna.tsinghua.edu.cn/centos/7.6.1810/updates/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - 
"Could not resolve host: mirrors.tuna.tsinghua.edu.cn; Unknown error"
Trying other mirror.

3.yum安装软件提示:Nothing to do (没事做)

有两种情况: 情况1:软件已经安装并且最新如下:

Package tree-1.6.0-10.el7.x86_64 already installed and latest version
tree软件包已经安装并且是最新版本
Package 2:vim-enhanced-7.4.160-5.el7.x86_64 already installed and latest version
Package 1:bash-completion-2.1-6.el7.noarch already installed and latest version
Nothing to do

情况2:软件名字写错或没有配置yum源导致找不到这个软件包

[root@oldboyedu60-lnb ~]# yum install treea -y
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirror.lzu.edu.cn
 * extras: mirrors.nwsuaf.edu.cn
 * updates: mirrors.nwsuaf.edu.cn
base                                                                                              | 3.6 kB  00:00:00     
extras                                                                                            | 3.4 kB  00:00:00     
updates                                                                                           | 3.4 kB  00:00:00     
No package treea available. 
#没有找到叫treea的软件包
Error: Nothing to do

情况3:你需要安装软件包而不是软件包里面的命令通过yum provides 查看命令属于哪个软件包

[root@oldboyedu59 ~]# yum install -y locate 
Loaded plugins: fastestmirror
Determining fastest mirrors
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
base                                                                                              | 3.6 kB  00:00:00     
extras                                                                                            | 3.4 kB  00:00:00     
updates                                                                                           | 3.4 kB  00:00:00     
(1/2): extras/7/x86_64/primary_db                                                                 | 187 kB  00:00:02     
(2/2): updates/7/x86_64/primary_db                                                                | 3.4 MB  00:00:04     
No package locate available.
Error: Nothing to do

[root@oldboyedu59 ~]# yum provides locate 
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
base/7/x86_64/filelists_db                                                                        | 7.1 MB  00:00:03     
extras/7/x86_64/filelists_db                                                                      | 236 kB  00:00:00     
updates/7/x86_64/filelists_db                                                                     | 2.7 MB  00:00:01     
mlocate-0.26-8.el7.x86_64 : An utility for finding files by name
Repo        : base
Matched from:
Filename    : /usr/bin/locate\
[root@oldboyedu59 ~]# yum install -y mlocate 
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * base: mirrors.aliyun.com
 * extras: mirrors.aliyun.com
 * updates: mirrors.aliyun.com
Resolving Dependencies
--> Running transaction check
---> Package mlocate.x86_64 0:0.26-8.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=========================================================================================================================
 Package                     Arch                       Version                           Repository                Size
=========================================================================================================================
Installing:
 mlocate                     x86_64                     0.26-8.el7                        base                     113 k

Transaction Summary
=========================================================================================================================
Install  1 Package

Total download size: 113 k
Installed size: 379 k
Downloading packages:
mlocate-0.26-8.el7.x86_64.rpm                                                                     | 113 kB  00:00:02     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : mlocate-0.26-8.el7.x86_64                                                                             1/1 
  Verifying  : mlocate-0.26-8.el7.x86_64                                                                             1/1 

Installed:
  mlocate.x86_64 0:0.26-8.el7                                                                                            

Complete!
[root@oldboyedu59 ~]# rpm -qa mlocate 
mlocate-0.26-8.el7.x86_64

4. Name or service not known 域名无法识别(无法上网）

原因1：DNS配置错误原因2：Linux无法上网原因 https://www.jianshu.com/p/0bc0b596c1a0

[root@oldboyedu59 ~]# ping baidu.com 
ping: baidu.com: Name or service not known
                 域名无法识别（无法将域名---->ip地址)

三. 修改系统基础配置类

1. 重启网卡报错 device not present

[root@oldboyusd ~]# systemctl restart network 
Job for network.service failed because the control process exited with error code.
 See "systemctl status network.service" and "journalctl -xe" for details.

查看详细错误原因 ·journalctl -xe·

Apr 01 15:31:05 oldboyusd.1 network[7816]: Bringing up interface etho:  
ERROR     : [/etc/sysconfig/network-scripts/ifup-eth] Device  does not seem to be present, delaying initialization.

Apr 01 15:31:05 oldboyusd.1 /etc/sysconfig/network-scripts/ifup-eth[8019]: 
Device  does not seem to be present, delaying initializatio

2. 修改主机名过程中,命令行中主机名没有变化

1# hostname命令修改主机名（临时重启服务器之后失效）

[root@oldboyedu59 ~]# hostname
oldboyedu59
[root@oldboyedu59 ~]# hostname oldboyedu59-lnb

2# 修改文件内容（写合同永久重启服务器之后生效）

vim /etc/hostname 
 oldboyedu59-lnb

3# 检查

[root@oldboyedu59 ~]# hostname
oldboyedu59-lnb
[root@oldboyedu59 ~]# cat /etc/hostname 
oldboyedu59-lnb

命令行中的主机名部分没有改变？

解决：重新登录下即可（断开连接，重新连接）

[root@oldboyedu59-lnb ~]#

3. unexpected EOF while looking for matching `"'

引号不成对

tail -2  /etc/profile 
alias net="cat /etc/sysconfig/network-scripts/ifcfg-eth0
export PS1="[\[\e[34;1m\]\u@\[\e[0m\]\[\e[32;1m\]\H\[\e[0m\] \[\e[31;1m\]\w\[\e[0m\]]\\$ "

[root@ssdz ~]# source /etc/profile
-bash: /etc/profile: line 78: unexpected EOF while looking for matching `"'
-bash: /etc/profile: line 79: syntax error: unexpected end of file

-bash: /etc/profile: line 78: unexpected EOF while looking for matching `"' /etc/profile 第78行出乎意料的结尾正在找 '"' 这个双引号的另一半

四. 用户类错误

1. user 'oldboy' already exists

用户已经存在

[root@oldboyedu59 ~]# useradd oldboy 
useradd: user 'oldboy' already exists

2. no such user

没有这个用户

[root@oldboyedu59 ~]# id lidao 
id: lidao: no such user

3.Only root can do that.

只有root用户可以使用非交互式设置密码方式

[oldboy@oldboyedu59 ~]$ echo 123456|passwd --stdin oldboy
Only root can do that.

4.Only root can specify a user name.

只有root用户运行passwd的时候后面能加上用户名普通用户默认只能运行passwd 不能加用户名修改自己的密码

[oldboy@oldboyedu59 ~]$ passwd oldboy 
passwd: Only root can specify a user name.

5. Creating mailbox file: File exists 和warning: the home directory already exists.

添加用户的时候提示:

Creating mailbox file: File exists 正在创建这个用户的邮箱:邮箱已经存在 warning: the home directory already exists. 这个用户的家目录已经存在

删除用户的时候，默认不删除家目录和邮箱. 再次添加就会提示家目录存在和邮箱存在

[root@oldboyedu59 ~]# id stu01 
uid=1005(stu01) gid=1006(stu01) groups=1006(stu01)
[root@oldboyedu59 ~]# userdel stu01
[root@oldboyedu59 ~]# useradd stu01 
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists

6.user nginx is currently used by process 7540

用户正在使用中被pid是7540的进程使用中

[root@web01 /usr/share/nginx/html/blog]#  usermod -u 2222   nginx 
usermod: user nginx is currently used by process 7540

五.脚本及定时任务

1. no crontab for root

root用户没有定时任务

[root@oldboyedu59 ~]# crontab -l
no crontab for root

root用户没有定时任务

2.no crontab for root - using an empty one

root用户没有定时任务，给root创建了1个新的这里实际上给root创建了定时任务文件 /var/spool/cron/root 空文件

3.crontab: installing new crontab

更新定时任务规则

4. bad xxx, errors in crontab file,can't install

错误的{分|时|日|月|周},定时任务文件中有错误，无法更新定时任务

分时日月周格式错误01

#mei liangfenzhong xianshi xitong shijian zhuijiadao /tmp/oldboy.txt
* /1 * * * date  >>/tmp/oldboy.txt

"/tmp/crontab.5UZIdI" 3L, 115C written
crontab: installing new crontab
"/tmp/crontab.5UZIdI":3: bad hour   3是第3行的意思,错误的小时 小时位置书写错误 
errors in crontab file, can't install.
Do you want to retry the same edit?

分时日月周格式错误02 时间范围书写错误 21-00错误改为 21-23,00 即可因为定时任务的小时为00-23

crontab -e 
#show time by liyy  at 20190101
#*/2 * * * * date >>/tmp/time.log

#
00  21-00 * * * date >>/tmp/time.log
00  21-00 * * * date >>/tmp/time.log
#00  21-23,00 * * * date >>/tmp/time.log

#backup /etc/ to /tmp by liyy  at 20190101
#00 00 * * *  sh  /server/scripts/bak-etc.sh

"/tmp/crontab.SpZAZH" 9L, 238C written
crontab: installing new crontab
"/tmp/crontab.SpZAZH":5: bad hour
errors in crontab file, can't install.
Do you want to retry the same edit?

5. You have new mail in /var/spool/mail/root

你有1个新邮件在/var/spool/mail/root

　　老男孩教育Linux培训班，从0基础到云计算架构，是一系列的实践课程。在Linux基础、云计算运维、Docker容器、集群与存储、数据库管理、安全技术、自动化运维、Python开发等方面的教学，帮助学生高效学习Linux技术，奠定坚实的理论基础和优秀的实践能力。帮助更多的Linux爱好者成为更好的Linux运维工程师。