系统优化 /etc/sysctl.conf

# sysctl settings are defined through files in
# /usr/lib/sysctl.d/, /run/sysctl.d/, and /etc/sysctl.d/.
#
# Vendors settings live in /usr/lib/sysctl.d/.
# To override a whole file, create a new file with the same in
# /etc/sysctl.d/ and put new settings there. To override
# only specific settings, add a file with a lexically later
# name in /etc/sysctl.d/ and put new settings there.
#
# For more information, see sysctl.conf() and sysctl.d().
#关闭ipv6

net.ipv6.conf.all.disable_ipv6 = 

net.ipv6.conf.default.disable_ipv6 = 

# 避免放大攻击

net.ipv4.icmp_echo_ignore_broadcasts = 

# 开启恶意icmp错误消息保护

net.ipv4.icmp_ignore_bogus_error_responses = 

#关闭路由转发

net.ipv4.ip_forward = 

net.ipv4.conf.all.send_redirects = 

net.ipv4.conf.default.send_redirects = 

#开启反向路径过滤

net.ipv4.conf.all.rp_filter = 

net.ipv4.conf.default.rp_filter = 

#处理无源路由的包

net.ipv4.conf.all.accept_source_route = 

net.ipv4.conf.default.accept_source_route = 

#关闭sysrq功能

kernel.sysrq = 

#core文件名中添加pid作为扩展名

kernel.core_uses_pid = 

# 开启SYN洪水攻击保护

net.ipv4.tcp_syncookies = 

#修改消息队列长度

kernel.msgmnb = 

kernel.msgmax = 

#设置最大内存共享段大小bytes

kernel.shmmax = 

kernel.shmall = 

#timewait的数量，默认180000

net.ipv4.tcp_max_tw_buckets = 

net.ipv4.tcp_sack = 

net.ipv4.tcp_window_scaling = 

net.ipv4.tcp_rmem =            

net.ipv4.tcp_wmem =            

net.core.wmem_default = 

net.core.rmem_default = 

net.core.rmem_max = 

net.core.wmem_max = 

#每个网络接口接收数据包的速率比内核处理这些包的速率快时，允许送到队列的数据包的最大数目

net.core.netdev_max_backlog = 

#限制仅仅是为了防止简单的DoS 攻击

net.ipv4.tcp_max_orphans = 

#未收到客户端确认信息的连接请求的最大值

net.ipv4.tcp_max_syn_backlog = 

net.ipv4.tcp_timestamps = 

#内核放弃建立连接之前发送SYNACK 包的数量

net.ipv4.tcp_synack_retries = 

#内核放弃建立连接之前发送SYN 包的数量

net.ipv4.tcp_syn_retries = 

#启用timewait 快速回收

net.ipv4.tcp_tw_recycle = 

#开启重用。允许将TIME-WAIT sockets 重新用于新的TCP 连接

net.ipv4.tcp_tw_reuse = 

net.ipv4.tcp_mem =   

net.ipv4.tcp_fin_timeout = 

#当keepalive 起用的时候，TCP 发送keepalive 消息的频度。缺省是2 小时

net.ipv4.tcp_keepalive_time = 

#允许系统打开的端口范围

net.ipv4.ip_local_port_range =     

#修改防火墙表大小，默认65536

#net.netfilter.nf_conntrack_max=

#net.netfilter.nf_conntrack_tcp_timeout_established=

# 确保无人能修改路由表

net.ipv4.conf.all.accept_redirects = 

net.ipv4.conf.default.accept_redirects = 

net.ipv4.conf.all.secure_redirects = 

net.ipv4.conf.default.secure_redirects =
vm.max_map_count =
fs.file-max=