我的电脑是不是被入侵了？

[hbcb]

我的电脑Red Hat Linux 9,内部IP:192.168.0.8,连接ADSL上网
近日发现root的邮件里面有以下的内容：

SSHD Killed: 11 Time(s)

SSHD Started: 11 Time(s)

Failed logins from these:
root/password from 218.6.145.91: 3 Time(s)
root/password from 61.33.21.250: 109 Time(s)
**Unmatched Entries**
Illegal user test from 218.6.145.91
Illegal user guest from 218.6.145.91
Illegal user admin from 218.6.145.91
Illegal user admin from 218.6.145.91
Illegal user user from 218.6.145.91
Illegal user test from 218.6.145.91
Illegal user test from 61.33.21.250
Illegal user guest from 61.33.21.250
Illegal user admin from 61.33.21.250
Illegal user admin from 61.33.21.250
Illegal user user from 61.33.21.250
Illegal user test from 61.33.21.250
Illegal user test from 61.33.21.250
Illegal user test from 61.33.21.250
Illegal user test from 61.33.21.250
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded
sshd -TERM succeeded
succeeded

---------------------- SSHD End -------------------------

请问我的系统是不是被入侵了？要怎样才可以关闭一切外网主动向本系统的连接呢？

[hbcb]

谢谢！~~~，已在防火墙级别中关掉这几个了

[yuanlei1978113]

可能有人想试图登陆你的机器,你可以关掉telnet,ftp,sshd等服务.