1、统计出/etc/passwd文件中其默认shell为非/sbin/nologin的用户个数,并将用户都显示出来
[root@centos8 ~]# cat /etc/passwd | grep -v /sbin/nologin |wc -l
5
[root@centos8 ~]# cat /etc/passwd | grep -v '/sbin/nologin'|cut -d: -f1
root
sync
shutdown
halt
xiaozz
2、查出用户UID最大值的用户名、UID及shell类型
[root@centos8 ~]# cat /etc/passwd |sort -nr -t: -k3 |cut -d: -f1,3,7 |head -1 nobody:65534:/sbin/nologin
3、统计当前连接本机的每个远程主机IP的连接数,并按从大到小排序
[root@centos8 ~]# netstat -atunl | tr -s " " |cut -d " " -f5 | cut -d: -f1 | uniq -c |sort -nr
6 0.0.0.0
5 0.0.0.0
5
4
1 and
1 Address
1 8.43.85.14
1 10.0.0.190
1 10.0.0.1
1 10.0.0.1
1 0.0.0.0
[root@centos8 ~]# netstat -atunl | grep "ESTABLISHED" |tr -s " " |cut -d " " -f5 | cut -d: -f1 | uniq -c | sort -nr
2 10.0.0.1
1 10.0.0.190
4、编写脚本disk.sh,显示当前硬盘分区中空间利用率最大的值
#!/bin/bash
echo "disk use max :`df -h|grep ^/dev/[svm]d |tr -s " " "%"|cut -d% -f5|sort -rn|head -n1`"
5、编写脚本 systeminfo.sh,显示当前主机系统信息,包括:主机名,IPv4地址,操作系统版本,内核版本,CPU型号,内存大小,硬盘大小
#!/bin/bash
RED="\E[1;31m"
GREEN="echo -e \E[1;32m"
END="\E[0m"
$GREEN----------------------Host systeminfo--------------------$END
echo -e "HOSTNAME: $RED`hostname`$END"
echo -e "IPADDR: $RED` ifconfig ens33|grep -Eo '([0-9]{1,3}\.){3}[0-9]
{1,3}' |head -n1`$END"
echo -e "OSVERSION: $RED`cat /etc/redhat-release`$END"
echo -e "KERNEL: $RED`uname -r`$END"
echo -e "CPU: $RED`lscpu|grep 'Model name'|tr -s ' '|cut -d : -f2`$END"
echo -e "MEMORY: $RED`free -h|grep Mem|tr -s ' ' : |cut -d : -f2`$END"
echo -e "DISK: $RED`lsblk |grep '^sd' |tr -s ' ' |cut -d " " -f4`$END"
$GREEN---------------------------------------------------------$END
[root@centos8 data]# bash systeminfo.sh
----------------------Host systeminfo--------------------
HOSTNAME: centos8.xiaozz.com
IPADDR:
OSVERSION: CentOS Linux release 8.4.2105
KERNEL: 4.18.0-305.3.1.el8.x86_64
CPU: Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz
Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz
MEMORY: 1.7Gi
DISK: 200G
20G
10G
6、20分钟内通关vimtutor(可参考https://yyqing.me/post/2017/2017-02-22-vimtutor-chinese-summary)
略!!!