Linux中根据访问日志统计访问量最高的前N个IP

前段时间面试中被问到如上问题，日常不怎么注意积累，以此谨记。

访问IP    页面
[nxuser@im440-zh test]$ vi log
135.252.172.181  page1
136.252.172.182  page1
135.252.172.181  page2
135.252.172.183  page1
136.252.172.184  page1
135.252.172.181  page3
135.252.172.185  page1
136.252.172.182  page2
135.252.172.183  page2
135.252.172.181  page4
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1
136.252.172.182  page1

代码实现：
1 [nxuser@im440-zh test]$ awk '{print $1}' log|sort |uniq -c|sort -r -n -k 1|head -n 3

结果：

      15 136.252.172.182
       4 135.252.172.181
       2 135.252.172.183

注意 第二sort 中 -n ,否则出现如下结果：

       4 135.252.172.181
       2 135.252.172.183
      15 136.252.172.182