1、client_body_timeout 10;-指令指定读取请求实体的超时时间。这里的超时是指一个请求实体没有进入读取步骤，如果连接超过这个时间而客户端没有任何响应，Nginx将返回一个”Request time out” (408)错误。
2、client_header_timeout 10;-指令指定读取客户端请求头标题的超时时间。这里的超时是指一个请求头没有进入读取步骤，如果连接超过这个时间而客户端没有任何响应，Nginx将返回一个”Request time out” (408)错误。
3、keepalive_timeout 5 5; – 参数的第一个值指定了客户端与服务器长连接的超时时间，超过这个时间，服务器将关闭连接。参数的第二个值（可选）指定了应答头中Keep-Alive: timeout=time的time值，这个值可以使一些浏览器知道什么时候关闭连接，以便服务器不用重复关闭，如果不指定这个参数，nginx不会在应答头中发送Keep-Alive信息。（但这并不是指怎样将一个连接“Keep-Alive”）参数的这两个值可以不相同。
4、send_timeout 10; 指令指定了发送给客户端应答后的超时时间，Timeout是指没有进入完整established状态，只完成了两次握手，如果超过这个时间客户端没有任何响应，nginx将关闭连接。

12、控制并发连接

limit_zone slimits $binary_remote_addr 5m;limit_conn slimits 5;

13、sysctl.conf配置

# Avoid a smurf attacknet.ipv4.icmp_echo_ignore_broadcasts = 1 # Turn on protection for bad icmp error messagesnet.ipv4.icmp_ignore_bogus_error_responses = 1 # Turn on syncookies for SYN flood attack protectionnet.ipv4.tcp_syncookies = 1 # Turn on and log spoofed, source routed, and redirect packetsnet.ipv4.conf.all.log_martians = 1net.ipv4.conf.default.log_martians = 1 # No source routed packets herenet.ipv4.conf.all.accept_source_route = 0net.ipv4.conf.default.accept_source_route = 0 # Turn on reverse path filteringnet.ipv4.conf.all.rp_filter = 1net.ipv4.conf.default.rp_filter = 1 # Make sure no one can alter the routing tablesnet.ipv4.conf.all.accept_redirects = 0net.ipv4.conf.default.accept_redirects = 0net.ipv4.conf.all.secure_redirects = 0net.ipv4.conf.default.secure_redirects = 0 # Don't act as a routernet.ipv4.ip_forward = 0net.ipv4.conf.all.send_redirects = 0net.ipv4.conf.default.send_redirects = 0 # Turn on execshildkernel.exec-shield = 1kernel.randomize_va_space = 1 # Tuen IPv6net.ipv6.conf.default.router_solicitations = 0net.ipv6.conf.default.accept_ra_rtr_pref = 0net.ipv6.conf.default.accept_ra_pinfo = 0net.ipv6.conf.default.accept_ra_defrtr = 0net.ipv6.conf.default.autoconf = 0net.ipv6.conf.default.dad_transmits = 0net.ipv6.conf.default.max_addresses = 1 # Optimization for port usefor LBs# Increase system file descriptor limitfs.file-max = 65535 # Allow for more PIDs (to reduce rollover problems); may break some programs 32768kernel.pid_max = 65536 # Increase system IP port limitsnet.ipv4.ip_local_port_range = 2000 65000 # Increase TCP max buffer size setable using setsockopt()net.ipv4.tcp_rmem = 4096 87380 8388608net.ipv4.tcp_wmem = 4096 87380 8388608 # Increase Linux auto tuning TCP buffer limits# min, default, and max number of bytes to use# set max to at least 4MB, or higher if you use very high BDP paths# Tcp Windows etcnet.core.rmem_max = 8388608net.core.wmem_max = 8388608net.core.netdev_max_backlog = 5000net.ipv4.tcp_window_scaling = 1