Skip to main content

Linux sysctl.conf 优化

可以通过/etc/sysctl.conf控制和配置Linux内核及网络设置。

sysctl配置​

避免放大攻击​

net.ipv4.icmp_echo_ignore_broadcasts = 1

开启恶意icmp错误消息保护​

net.ipv4.icmp_ignore_bogus_error_responses = 1

开启SYN洪水攻击保护​

net.ipv4.tcp_syncookies = 1

开启并记录欺骗，源路由和重定向包​

net.ipv4.conf.all.log_martians = 1
net.ipv4.conf.default.log_martians = 1

处理无源路由的包​

net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.default.accept_source_route = 0

开启反向路径过滤​

net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.default.rp_filter = 1

确保无人能修改路由表​

net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv4.conf.all.secure_redirects = 0
net.ipv4.conf.default.secure_redirects = 0

不充当路由器​

net.ipv4.ip_forward = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0

开启execshild​

kernel.exec-shield = 1
kernel.randomize_va_space = 1

IPv6设置​

net.ipv6.conf.default.router_solicitations = 0
net.ipv6.conf.default.accept_ra_rtr_pref = 0
net.ipv6.conf.default.accept_ra_pinfo = 0
net.ipv6.conf.default.accept_ra_defrtr = 0
net.ipv6.conf.default.autoconf = 0
net.ipv6.conf.default.dad_transmits = 0
net.ipv6.conf.default.max_addresses = 1

优化LB使用的端口​

增加系统文件描述符限制​

fs.file-max = 65535

允许更多的PIDs​

(减少滚动翻转问题); may break some programs 32768

kernel.pid_max = 65536

增加系统IP端口限制​

net.ipv4.ip_local_port_range = 2000 65000

增加TCP最大缓冲区大小​

net.ipv4.tcp_rmem = 4096 87380 8388608
net.ipv4.tcp_wmem = 4096 87380 8388608
  • 增加Linux自动调整TCP缓冲区限制
  • 最小，默认和最大可使用的字节数
  • 最大值不低于4MB，如果你使用非常高的BDP路径可以设置得更高

Tcp窗口等​

net.core.rmem_max = 8388608
net.core.wmem_max = 8388608
net.core.netdev_max_backlog = 5000
net.ipv4.tcp_window_scaling = 1