Linux每日小技巧---ss命令
ss命令 ss是Socket Statistics的缩写。顾名思义，ss命令可以用来获取socket统计信息，它可以显示和netstat类似的内容。但ss的优势在于它能够显示更多更详细的有关TCP和连接状态的信息，而且比netstat更快速更高效
例如查看22端口状态 ：
[tidb@:vg_adn_tidbCkhsTest:54.158.254.36:172.31.30.62 ~/tidb-ansible]$ss -tnl | grep 22 LISTEN 0 128 *:22 *:* LISTEN 0 128 :::22 :::*
ss命令比netstat命令还有更强大的过滤功能，非常方便查询使用。
1、查询连接状态为ESTABLISHED的端口连接：
[root@ELK-chaofeng ~]#ss -tan state ESTABLISHED Recv-Q Send-Q Local Address:Port Peer Address:Port 0 0 127.0.0.1:36134 127.0.0.1:3306 40 0 127.0.0.1:10050 127.0.0.1:55180 0 0 127.0.0.1:36122 127.0.0.1:3306 0 0 127.0.0.1:36112 127.0.0.1:3306 0 0 127.0.0.1:36124 127.0.0.1:3306 0 0 127.0.0.1:36118 127.0.0.1:3306 0 0 127.0.0.1:36152 127.0.0.1:3306 0 0 127.0.0.1:36142 127.0.0.1:3306 0 0 127.0.0.1:36110 127.0.0.1:3306 0 0 127.0.0.1:44630 127.0.0.1:3306 0 0 172.17.36.151:51274 100.100.80.176:8000 0 0 127.0.0.1:55172 127.0.0.1:10050 0 0 127.0.0.1:55180 127.0.0.1:10050 32 0 127.0.0.1:10050 127.0.0.1:55176 0 0 172.17.36.151:42392 100.100.30.25:80 0 0 127.0.0.1:10050 127.0.0.1:55172
查询连接状态为LISTEN的端口连接：
[root@ELK-chaofeng ~]#ss -tan state LISTENING Recv-Q Send-Q Local Address:Port Peer Address:Port 0 128 *:80 *:* 0 128 *:22 *:* 0 10 127.0.0.1:15772 *:* 4 128 *:10050 *:* 0 128 *:10051 *:* 0 128 :::3306 :::* 0 128 :::10050 :::* 0 128 :::10051 :::*
2、过滤功能，过滤出源端口为10050的端口连接状态
[root@ELK-chaofeng ~]#ss -tan '( sport = :10050 or dport = :10050 )' State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 1 128 *:10050 *:* ESTAB 0 0 127.0.0.1:10050 127.0.0.1:55548 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55482 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55474 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55530 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55472 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55522 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55448 ESTAB 0 0 127.0.0.1:55550 127.0.0.1:10050 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55534 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55540 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55514 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55536 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55510 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55526 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55422 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55498 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55438 TIME-WAIT 0 0 127.0.0.1:10050 127.0.0.1:55506
