1. #/bin/bash
    2. # 设置时区并同步时间
    3. ln -s /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
    4. if ! crontab -l |grep ntpdate &>/dev/null ; then
    5.     (echo "* 1 * * * ntpdate time.windows.com >/dev/null 2>&1";crontab -l) |crontab
    6. fi
    8. # 禁用selinux
    9. sed -i '/SELINUX/{s/permissive/disabled/}' /etc/selinux/config
    11. # 关闭防火墙
    12. if egrep "7.[0-9]" /etc/redhat-release &>/dev/null; then
    13.     systemctl stop firewalld
    14.     systemctl disable firewalld
    15. elif egrep "6.[0-9]" /etc/redhat-release &>/dev/null; then
    16.     service iptables stop
    17.     chkconfig iptables off
    18. fi
    20. # 历史命令显示操作时间
    21. if ! grep HISTTIMEFORMAT /etc/bashrc; then
    22.     echo 'export HISTTIMEFORMAT="%F %T `whoami` "' >> /etc/bashrc
    23. fi
    25. # SSH超时时间
    26. if ! grep "TMOUT=600" /etc/profile &>/dev/null; then
    27.     echo "export TMOUT=600" >> /etc/profile
    28. fi
    30. # 禁止root远程登录
    31. sed -i 's/#PermitRootLogin yes/PermitRootLogin no/' /etc/ssh/sshd_config
    33. # 禁止定时任务向发送邮件
    34. sed -i 's/^MAILTO=root/MAILTO=""/' /etc/crontab
    36. # 设置最大打开文件数
    37. if ! grep "* soft nofile 65535" /etc/security/limits.conf &>/dev/null; then
    38.     cat >> /etc/security/limits.conf << EOF
    39.     * soft nofile 65535
    40.     * hard nofile 65535
    41. EOF
    42. fi
    44. # 系统内核优化
    45. cat >> /etc/sysctl.conf << EOF
    46. net.ipv4.tcp_syncookies = 1
    47. net.ipv4.tcp_max_tw_buckets = 20480
    48. net.ipv4.tcp_max_syn_backlog = 20480
    49. net.core.netdev_max_backlog = 262144
    50. net.ipv4.tcp_fin_timeout = 20
    51. EOF
    53. # 减少SWAP使用
    54. echo "0" > /proc/sys/vm/swappiness
    56. # 安装系统性能分析工具及其他
    57. yum install gcc make autoconf vim sysstat net-tools iostat if