Linux系统管理 安全篇 之开放端口

查看系统中开放的端口，关闭不需要的端口和程序，如下例中操作流程：
1. 查看对外开启的端口:
[root@mail ~]# nmap 127.0.0.1 #注：此处应该换作公网ip
Starting Nmap 4.11 ( http://www.insecure.org/nmap/ ) at 2010-04-20 11:06 CST
Interesting ports on 127.0.0.1
Not shown: 1668 closed ports
PORT     STATE SERVICE
22/tcp   open  ssh
25/tcp   open  smtp
80/tcp   open  http
1010/tcp open  unknown
2. 对不明端口进行查访
[root@mail ~]# netstat -anlp | grep 1010
tcp        0      0 0.0.0.0:1010                0.0.0.0:*                   LISTEN      3796/rpc.statd
#
#[root@mail ~]# lsof -p 3796
#
#
[root@mail init.d]# which rpc.statd
/sbin/rpc.statd
[root@mail ~]# rpm -qf /sbin/rpc.statd
nfs-utils-1.0.9-40.el5
[root@mail init.d]# ll /etc/init.d/nfs*
-rwxr-xr-x 1 root root 4668 Jan 21  2009 /etc/init.d/nfs
-rwxr-xr-x 1 root root 3465 Jan 21  2009 /etc/init.d/nfslock
[root@mail init.d]# service nfs status
rpc.mountd is stopped
nfsd is stopped
rpc.rquotad is stopped
[root@mail ~]# /etc/init.d/nfslock status
rpc.statd (pid 3796) is running...
3. 关闭不相干的应用
[root@mail init.d]# service nfslock
Usage: /etc/init.d/nfslock {start|stop|status|restart|probe|condrestart}
[root@mail init.d]# service nfslock stop
Stopping NFS statd:                                        [  OK  ]
4. 关闭不相干的服务
[root@mail init.d]# chkconfig --level 345 nfslock off