二十一、编写简单脚本之检测磁盘空间

使用du命令

[root@tzPC 24Unit]# du -sh /home/*
12K    /home/Christine

-S选项可以统计每个目录以及他们子目录的大小

[root@tzPC 24Unit]# du -Sh /var/log/
38M    /var/log/audit
28K    /var/log/tuned
16K    /var/log/samba/old
0    /var/log/samba/cores/smbd
0    /var/log/samba/cores
0    /var/log/samba

排序

-r选项允许按数字排序，-n选项从大到小排序

[root@tzPC 24Unit]# du -Sh /var/log/ | sort -rn
38M    /var/log/audit
28K    /var/log/tuned
16K    /var/log/samba/old
2.1M    /var/log/anaconda
2.0M    /var/log/
0    /var/log/samba/cores/smbd
0    /var/log/samba/cores
0    /var/log/samba
0    /var/log/rhsm

使用sed编辑器对结果添加行号

=命令添加行号，N命令让行号跟文本位于同一行，筛选前面11行结果

[root@tzPC 24Unit]# du -Sh /var/log/ | sort -rn | sed '{11,$D;=}' | sed 'N;s/\n/ /'
1 38M    /var/log/audit
2 28K    /var/log/tuned
3 16K    /var/log/samba/old
4 2.1M    /var/log/anaconda
5 2.0M    /var/log/
6 0    /var/log/samba/cores/smbd
7 0    /var/log/samba/cores
8 0    /var/log/samba
9 0    /var/log/rhsm

使用gawk命令给每行添加一个：给每行文本字段间放置一个制表符

[root@tzPC 24Unit]# du -Sh /var/log/ |
> sort -rn |
> sed '{11,$D;=}' |
> sed 'N;s/\n/ /' |
> gawk '{printf $1 ":" "\t" $2 "\t" $3 "\n"}'
1:    38M    /var/log/audit
2:    28K    /var/log/tuned
3:    16K    /var/log/samba/old
4:    2.1M    /var/log/anaconda
5:    2.0M    /var/log/
6:    0    /var/log/samba/cores/smbd
7:    0    /var/log/samba/cores
8:    0    /var/log/samba
9:    0    /var/log/rhsm

设置变量指定要监测的目录

CHECK_DIRECTORIES'"/var/log /home"

使用for循环遍历CHECK_DIRECTORIES变量每个目录，并使用du统计大小

for DIR_CHECK in $CHECK_DIRECTORIES
do
[...]
    du -Sh $DIR_CHECK
[...]
done

使用exec命令输出报告

DATE=$(date '+%m%d%y')
exec > disk_space_$DATE.rpt

整个脚本如下

[root@tzPC 24Unit]# cat dir_check.sh 
#!/bin/bash
CHECK_DIRECTORIES="/var/log /home"
#Main Script
DATE=$(date '+%m%d%y')
exec > disk_space_$DATE.rpt
echo "Top Ten Disk Space Usage" #前十磁盘空间使用
echo "for $CHECK_DIRECTORIES directories"
for DIR_CHECK in $CHECK_DIRECTORIES
do
    echo
    echo "The $DIR_CHECK Directory:"
    du -Sh $DIR_CHECK 2>/dev/null |
    sort -rn |
    sed '{11,$D;=}' |
    sed 'N;s/\n/ /' |
    gawk '{printf $1 ":" "\t" $2 "\t" $3 "\n"}'
done
exit

运行效果

[root@tzPC 24Unit]# bash dir_check.sh 
[root@tzPC 24Unit]# cat disk_space_090720.rpt 
Top Ten Disk Space Usage
for /var/log /home directories

The /var/log Directory:
1:    38M    /var/log/audit
2:    28K    /var/log/tuned
3:    16K    /var/log/samba/old
4:    2.1M    /var/log/anaconda
5:    2.0M    /var/log
6:    0    /var/log/samba/cores/smbd
7:    0    /var/log/samba/cores
8:    0    /var/log/samba
9:    0    /var/log/rhsm

The /home Directory:
1:    12K    /home/tz-3
2:    12K    /home/tz-2
3:    12K    /home/tz-1
4:    12K    /home/tz
5:    12K    /home/Christine
6:    0    /home

 学习来自：《Linux命令行与Shell脚本大全 第3版》第24章