描述
假设Nginx的日志存储在nowcoder.txt里，内容如下：
192.168.1.20 - - [21/Apr/2020:14:12:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.21 - - [21/Apr/2020:15:00:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.22 - - [21/Apr/2020:21:21:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.23 - - [21/Apr/2020:22:10:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.24 - - [22/Apr/2020:15:00:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.25 - - [22/Apr/2020:15:26:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.20 - - [23/Apr/2020:08:05:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Baiduspider" 192.168.1.21 - - [23/Apr/2020:09:20:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.22 - - [23/Apr/2020:10:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.22 - - [23/Apr/2020:10:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.20 - - [23/Apr/2020:14:12:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.21 - - [23/Apr/2020:15:00:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.22 - - [23/Apr/2020:15:00:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Baiduspider" 192.168.1.25 - - [23/Apr/2020:16:15:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.24 - - [23/Apr/2020:20:27:49 +0800] "GET /2/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.25 - - [23/Apr/2020:20:27:49 +0800] "GET /3/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.20 - - [23/Apr/2020:20:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.21 - - [23/Apr/2020:20:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.22 - - [23/Apr/2020:20:27:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.22 - - [23/Apr/2020:22:10:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0" 192.168.1.21 - - [23/Apr/2020:23:59:49 +0800] "GET /1/index.php HTTP/1.1" 404 490 "-" "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:45.0) Gecko/20100101 Firefox/45.0"
现在需要编写Shell脚本统计每分钟的请求数，并且按照请求数降序排序。你的脚本应该输出：
5 20:27 4 15:00 2 22:10 2 14:12 2 10:27 1 23:59 1 21:21 1 16:15 1 15:26 1 09:20 1 08:05
具体代码实现：
#!/bin/bash
cat nowcoder.txt | awk '{print($4)}' | awk -F ":" '{print($2 ":" $3)}' | sort -n | uniq -c | sort -rn | awk '{print $1 " " $2}'解题思路：
1.使用awk取出第四个域的值（也就是日期时间那个）
2.awk -F 对取出的值进行处理，以":" 为分隔符，取第二个和第三个域的值
3.最后进行去重排序（逆序），再按题目要求格式输出
