script089
题目
注：题目来源于 SHELL32 netstat练习4-输出和3306端口建立连接总的各个状态的数目 。
假设 netstat 命令运行的结果我们存储在 nowcoder.txt 里，格式如下：
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:6160 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 172.16.56.200:41856 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:49822 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:49674 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:42316 172.16.34.143:3306 ESTABLISHED
tcp 0 0 172.16.56.200:44076 172.16.240.74:6379 ESTABLISHED
tcp 0 0 172.16.56.200:49656 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:58248 100.100.142.4:80 TIME_WAIT
tcp 0 0 172.16.56.200:50108 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:41944 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:35548 100.100.32.118:80 TIME_WAIT
tcp 0 0 172.16.56.200:39024 100.100.45.106:443 TIME_WAIT
tcp 0 0 172.16.56.200:41788 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:58260 100.100.142.4:80 TIME_WAIT
tcp 0 0 172.16.56.200:41812 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:41854 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:58252 100.100.142.4:80 TIME_WAIT
tcp 0 0 172.16.56.200:49586 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:41754 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:50466 120.55.222.235:80 TIME_WAIT
tcp 0 0 172.16.56.200:38514 100.100.142.5:80 TIME_WAIT
tcp 0 0 172.16.56.200:49832 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:52162 100.100.30.25:80 ESTABLISHED
tcp 0 0 172.16.56.200:50372 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:50306 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:49600 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:41908 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:60292 100.100.142.1:80 TIME_WAIT
tcp 0 0 172.16.56.200:37650 100.100.54.133:80 TIME_WAIT
tcp 0 0 172.16.56.200:41938 172.16.34.144:3306 ESTABLISHED
tcp 0 0 172.16.56.200:49736 172.16.0.24:3306 ESTABLISHED
tcp 0 0 172.16.56.200:41890 172.16.34.144:3306 ESTABLISHED
udp 0 0 127.0.0.1:323 0.0.0.0:*
udp 0 0 0.0.0.0:45881 0.0.0.0:*
udp 0 0 127.0.0.53:53 0.0.0.0:*
udp 0 0 172.16.56.200:68 0.0.0.0:*
udp6 0 0 ::1:323 :::*
raw6 0 0 :::58 :::* 7
现在需要你输出和本机3306端口建立连接的各个状态的数目，按照以下格式输出：
- TOTAL_IP表示建立连接的ip数目
- TOTAL_LINK表示建立连接的总数目
TOTAL_IP 3
ESTABLISHED 20
TOTAL_LINK 20
脚本一
通过 grep 命令使用正则表达式匹配正确行，再使用 awk 命令提取指定列，最后使用 wc 命令统计行数。
#!/bin/bash
total_ip_count=$(grep ":3306" nowcoder.txt | awk '{print $5}' | sed 's/:3306//' | sort | uniq | wc -l)
established_count=$(grep -E ":3306.*ESTABLISHED" nowcoder.txt | awk '{print $5}' | wc -l)
total_link_count=$(grep -E ":3306.*ESTABLISHED" nowcoder.txt | wc -l)
echo "TOTAL_IP ${total_ip_count}"
echo "ESTABLISHED ${established_count}"
echo "TOTAL_LINK ${total_link_count}"
脚本二
使用 awk 命令编程实现。
awk '{
# 如果第一个字段是 tcp，并且 第五个字段包含字符串 3306
if ($1 == "tcp" && $5 ~ /3306/) {
# 则判断第六个字段是否是 ESTABLISHED 状态
if ($6 == "ESTABLISHED") {
# 该变量记录 ESTABLISHED 的出现次数
es++
}
# 记录总连接数
ans++
# 用关联数组记录不重复 IP，数组的长度就是 IP 的个数，这里元素值为零没有实际含义
arr[$5]=0
}
} END {
printf("TOTAL_IP %d\nESTABLISHED %d\nTOTAL_LINK %d", length(arr), es, ans)
}'
