介紹
lsof，List Open Files 列出當前系統打開文件的工具。在linux環境下，任何事物都以文件的形式存在，通過文件不僅僅可以訪問常規數據，還可以訪問網絡連接和硬件(lsof強大原因)。所以如傳輸控制協議 (TCP) 和用戶數據報協議 (UDP) 套接字等，系統在後臺都爲該應用程序分配了一個文件描述符，無論這個文件的本質如何，該文件描述符爲應用程序與基礎操作系統之間的交互提供了通用接口。因 爲應用程序打開文件的描述符列表提供了大量關於這個應用程序本身的信息，因此通過lsof工具能夠查看這個列表對系統監測以及排錯將是很有幫助的。
檢查是否安裝，如沒有使用yum install lsof進行安裝
[root@bogon ~]# lsof
-bash: lsof: command not found
/*** 註釋:表示當前centos中沒有lsof，使用如下命令進行安裝 **/
[root@bogon ~]# yum install lsof
Loaded plugins: fastestmirror
base | 3.6 kB 00:00:00
extras | 3.4 kB 00:00:00
updates | 3.4 kB 00:00:00
extras/7/x86_64/primary_db | 200 kB 00:00:00
Loading mirror speeds from cached hostfile
* base: mirrors.tuna.tsinghua.edu.cn
* extras: mirrors.tuna.tsinghua.edu.cn
* updates: mirrors.tuna.tsinghua.edu.cn
Resolving Dependencies
--> Running transaction check
---> Package lsof.x86_64 0:4.87-6.el7 will be installed
--> Finished Dependency Resolution
Dependencies Resolved
===========================================================================================================
Package Arch Version Repository Size
===========================================================================================================
Installing:
lsof x86_64 4.87-6.el7 base 331 k
Transaction Summary
===========================================================================================================
Install 1 Package
Total download size: 331 k
Installed size: 927 k
Is this ok [y/d/N]: y
Downloading packages:
lsof-4.87-6.el7.x86_64.rpm | 331 kB 00:00:00
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Installing : lsof-4.87-6.el7.x86_64 1/1
Verifying : lsof-4.87-6.el7.x86_64 1/1
Installed:
lsof.x86_64 0:4.87-6.el7
Complete!
驗證是否安裝成功
[root@bogon ~]# lsof -i:8080
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
java 1069 root 49u IPv6 19174 0t0 TCP *:webcache (LISTEN)