性能檢測命令 top free df uptime last history vmstat 1 sar iostat netstat -an nmap -sT -O localhost uname -r chkconfig --list w du -ms netstat -n -p -t | grep SYN_RECV | grep :80 | wc -l ps -aux | grep imap kill -9 <PID> killall imapd 加入於2006.11.21 less /etc/sysconfig/iptables less /etc/ssh/sshd_config less /etc/passwd //look for new user less /etc/group //look for new group or if have new user in root group less /etc/rc.d/rc.local
Monitor Opening Port # nmap –sT –O localhost 834/tcp open unknown
# cat /etc/services | grep 834 //查看834埠是否和任何已知服務相關 # netstat –anp | grep 834 //p選項揭示了打開834埠的進程ID（PID） # lsof –i | grep 834 查找或刪除正在使用某文件的進程
fuser filename
fuser -k filename yum clear all yum -y update if you find "Error: Cannot find a valid baseurl for repo", try to ping [url]www.centos.org[/url] and check iptables policy. if you find "You may also check that you have the correct GPG keys installed",then: uname -r find / -name RPM-GPG-KEY-* //number:version about CentOS rpm --import /usr/share/doc/CentOS-release-3/RPM-GPG-KEY-centos3 //change IP address: vi /etc/sysconfig/network-scripts/ifcfg-eth0 //add default gateway route add default gw 192.168.18.1 dev eth0
