Linux作业(3)

发布时间：2019-09-12 08:00:21编辑：auto阅读（1747）

1、找出/etc/rc.d/init.d/functions文件中某单词后面跟一组小括号的行，形如：hello()；

[root@localhost~]# ls /etc/rc.d/init.d/
functions  netconsole  network README
[root@localhost ~]# grep -o "\<.*\>()"/etc/rc.d/init.d/functions
checkpid()
__pids_var_run()
__pids_pidof()
daemon()
killproc()
pidfileofproc()
pidofproc()
status()
echo_success()
echo_failure()
echo_passed()
echo_warning()
update_boot_stage()
success()
failure()
passed()
warning()
action()
strstr()

2、使用echo命令输出一个绝对路径，使用grep取出其基名；

[root@localhost~]#  echo "/etc/rc.d/init.d/functions"| grep -E -o "[^/]+$"
functions

扩展：取出其路径名

[root@localhost~]# echo "/etc/rc.d/init.d/functions" | grep -E -o "^/.*/"
/etc/rc.d/init.d/

3、找出ifconfig命令结果中的1-255之间数字；

[root@localhost ~]# ifconfig

eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

       inet 192.168.2.108  netmask255.255.255.0  broadcast 192.168.2.255

       inet6 fe80::20c:29ff:fe0d:4a8b prefixlen 64  scopeid0x20<link>

       ether 00:0c:29:0d:4a:8b txqueuelen 1000  (Ethernet)

       RX packets 419  bytes 41325 (40.3KiB)

       RX errors 0  dropped 0  overruns 0 frame 0

       TX packets 337  bytes 46637 (45.5KiB)

       TX errors 0  dropped 0 overruns0  carrier 0  collisions 0

 

lo:flags=73<UP,LOOPBACK,RUNNING>  mtu65536

       inet 127.0.0.1  netmask 255.0.0.0

       inet6 ::1  prefixlen 128  scopeid 0x10<host>

       loop  txqueuelen 0  (Local Loopback)

       RX packets 4  bytes 340 (340.0 B)

       RX errors 0  dropped 0  overruns 0 frame 0

       TX packets 4  bytes 340 (340.0 B)

       TX errors 0  dropped 0 overruns0  carrier 0  collisions 0

 

virbr0:flags=4099<UP,BROADCAST,MULTICAST> mtu 1500

       inet 192.168.122.1  netmask255.255.255.0  broadcast 192.168.122.255

       ether 52:54:00:47:81:6c txqueuelen 0  (Ethernet)

       RX packets 0  bytes 0 (0.0 B)

       RX errors 0  dropped 0  overruns 0 frame 0

       TX packets 0  bytes 0 (0.0 B)

       TX errors 0  dropped 0 overruns0  carrier 0  collisions 0

 

[root@localhost ~]#ifconfig | grep -E -o "\<([0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\>"
192
168
2
108
255
255
255
0
192
168
2
255
64
29
38
5
0
0
0
0
40
8
0
0
0
0
0
73
127
0
0
1
255
0
0
0
1
128
0
4
0
0
0
0
0
4
0
0
0
0
0
0
192
168
122
1
255
255
255
0
192
168
122
255
52
54
47
81
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0

4、查找当前系统上没有属主或属组的文件；

[root@localhost~]# find / -nouser -o -nogroup
/home/mandriva
/home/mandriva/.bash_logout
/home/mandriva/.bash_profile
/home/mandriva/.bashrc
/home/mandriva/.mozilla
/home/mandriva/.mozilla/extensions
/home/mandriva/.mozilla/plugins
find: ‘/proc/3244/task/3244/fd/6’: 没有那个文件或目录
find:‘/proc/3244/task/3244/fdinfo/6’: 没有那个文件或目录
find: ‘/proc/3244/fd/6’: 没有那个文件或目录
find:‘/proc/3244/fdinfo/6’: 没有那个文件或目录
/var/spool/mail/mandriva
[root@localhost ~]#

进一步：查找当前系统上没有属主或属组，且最近3天内曾被访问过的文件或目录；

[root@localhost ~]# find / \( -nouser -o-nogroup \) -a -atime -3

/home/mandriva

/home/mandriva/.mozilla

/home/mandriva/.mozilla/extensions

/home/mandriva/.mozilla/plugins

find: ‘/proc/3254/task/3254/fd/6’: 没有那个文件或目录

find: ‘/proc/3254/task/3254/fdinfo/6’: 没有那个文件或目录

find: ‘/proc/3254/fd/6’: 没有那个文件或目录

find: ‘/proc/3254/fdinfo/6’: 没有那个文件或目录

5、查找/etc目录下大于1M，且类型为普通文件的所有文件；

[root@localhost ~]# find /etc -size +1M -a-type f -ls

4239312 6852 -r--r--r--   1 root    root      7014922 12月 11 00:24/etc/udev/hwdb.bin

202385046 3772 -rw-r--r--   1 root    root      3858924 11月 21  2015 /etc/selinux/targeted/policy/policy.29

4083229 1336 -rw-r--r--   1 root    root      1367395 3月  6  2015/etc/brltty/zh-tw.ctb

[root@localhost ~]#

6、查找/etc/init.d/目录下，所有用户都有执行权限，且其它用户有写权限的文件；

[root@localhost ~]# find /etc/init.d/ -perm/113 -ls

201494444   0 drwxr-xr-x   2 root     root           66 12月 10 00:22/etc/init.d/

201868855   4 -rwxr-xr-x   1 root     root         2989 9月 16  2015 /etc/init.d/netconsole

201868856   8 -rwxr-xr-x   1 root     root         6630 9月 16  2015 /etc/init.d/network

7、查找/etc目录下最近一周内其内容被修改过，且不属于root或hadoop的文件；

[root@localhost~]# find /etc/ -not \( -user root -o -user hadoop \) -atime -7 -ls
find: 用户名‘hadoop’ 未知
[root@localhost ~]# find/etc/ -not \( -user root -o -user bin \) -atime -7 -ls
134780546    0 drwx------   2 polkitd root           63 12月 10 00:21 /etc/polkit-1/rules.d
136093649    0 drwx--x--x   2 sssd    sssd            6 8月 3 00:58 /etc/sssd
[root@localhost ~]#

8、复制/etc/rc.d/rc.sysinit文件至/tmp目录，将/tmp/rc.sysinit文件中的以至少一个空白字符开头的行的行首加#；

[root@localhost~]# ls /etc/rc.d/
init.d  rc0.d  rc1.d  rc2.d  rc3.d  rc4.d  rc5.d  rc6.d  rc.local
[root@localhost ~]#

[root@localhost~]# cp /etc/rc.d/rc.local /tmp/
[root@localhost ~]# ls /tmp/
mytest2   systemd-private-62113d01174b48f3b9b96b264b53cd52-cups.service-x1z7b8
rc.local  systemd-private-62113d01174b48f3b9b96b264b53cd52-vmtoolsd.service-pkrcv0
[root@localhost ~]# sed -i 's/\(^[[:space:]]\)/#\1/g' /tmp/rc.local

9、删除/tmp/rc.sysinit文件中的以#开头，且后面跟了至少一个空白字符的行行的#和空白字符

[root@localhost~]# cat /etc/rc.local
#!/bin/bash
# THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES
#
# It is highly advisable to create own systemd services or udev rules
# to run scripts during boot instead of using this file.
#
# In contrast to previous versions due to parallel execution during boot
# this script will NOT be run after all other services.
#
# Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure
# that this script will be executed during boot.

touch /var/lock/subsys/local
[root@localhost ~]# cp /etc/rc.d/rc.local /tmp/
[root@localhost ~]# ls /tmp/
mytest2   systemd-private-62113d01174b48f3b9b96b264b53cd52-cups.service-x1z7b8
rc.local  systemd-private-62113d01174b48f3b9b96b264b53cd52-vmtoolsd.service-pkrcv0



[root@localhost~]# sed -i 's/^#[[:space:]]\+//g' /tmp/rc.local
[root@localhost ~]# cat /tmp/rc.local
#!/bin/bash
THIS FILE IS ADDED FOR COMPATIBILITY PURPOSES
#
It is highly advisable to create own systemd services or udev rules
to run scripts during boot instead of using this file.
#
In contrast to previous versions due to parallel execution during boot
this script will NOT be run after all other services.
#
Please note that you must run 'chmod +x /etc/rc.d/rc.local' to ensure
that this script will be executed during boot.

touch /var/lock/subsys/local
[root@localhost ~]#

 

10、将/etc/yum.repos.d/CentOS-Media.repo文件中所有的enabled=0或gpgcheck=0的最后的0修改为1；

[root@localhost~]# sed 's/enabled=0/enabled=1/g;s/gpgcheck=1/gpgcheck=2/g;'/etc/yum.repos.d/CentOS-Media.rep

 

11、每周2，4，6备份/var/log/messages文件至/backup/messages_logs/目录中，保存的文件名形如messages-20161202

[root@localhost~]# crontab -e

00 00 * *2,4,6 cp -r /var/log/messages /backup/messages_logs/messages-$(date +/%Y/%m/%d)

12、每天每两小时取当前系统/proc/meminfo文件中的所有以S开头的信息至/stats/memory.txt文件中

[root@localhost~]# crontab -e

00 */2 * * *cat /proc/meminfo |grep "^S" >> /stats/memory.txt

13、写一个脚本创建10用户user10-user19；密码同用户名；

[root@localhost~]# vi test02

 

#!/bin/sh

for i in {10..19};do

id user$i &>/dev/dull

if [ $? -eq 0 ];then

   echo "user$i exits"

else

   useradd user$i

   echo "user$i"| passwd --stdin user$i

   echo "user$i added"

fi

done

 

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