最大檔案描述符 

ulimit -SHn 1024000 
echo "ulimit -SHn 1024000" >> /etc/rc.d/rc.local 
source /etc/rc.d/rc.local

核心引數優化/etc/sysctl.conf

#關閉ipv6
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1

#決定檢查過期多久鄰居條目
net.ipv4.neigh.default.gc_stale_time=120

#使用arp_announce / arp_ignore解決ARP對映問題
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.all.arp_announce=2
net.ipv4.conf.lo.arp_announce=2 # 避免放大攻擊
net.ipv4.icmp_echo_ignore_broadcasts = 1 # 開啟惡意icmp錯誤訊息保護
net.ipv4.icmp_ignore_bogus_error_responses = 1

#處理無源路由的包
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.default.accept_source_route = 0

#core檔名中新增pid作為副檔名
kernel.core_uses_pid = 1 # 開啟SYN洪水攻擊保護
net.ipv4.tcp_syncookies = 1

#修改訊息佇列長度
kernel.msgmnb = 65536
kernel.msgmax = 65536

#timewait的數量，預設180000
net.ipv4.tcp_max_tw_buckets = 6000
net.ipv4.tcp_sack = 1
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_rmem = 4096 87380 4194304
net.ipv4.tcp_wmem = 4096 16384 4194304
net.core.wmem_default = 8388608
net.core.rmem_default = 8388608
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216

#限制僅僅是為了防止簡單的DoS 攻擊
net.ipv4.tcp_max_orphans = 3276800

#未收到客戶端確認資訊的連線請求的最大值
net.ipv4.tcp_max_syn_backlog = 262144
net.ipv4.tcp_timestamps = 0

#核心放棄建立連線之前傳送SYNACK 包的數量
net.ipv4.tcp_synack_retries = 1

#核心放棄建立連線之前傳送SYN 包的數量
net.ipv4.tcp_syn_retries = 1

#啟用timewait 快速回收
net.ipv4.tcp_tw_recycle = 1

#開啟重用。允許將TIME-WAIT sockets 重新用於新的TCP 連線
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_mem = 94500000 915000000 927000000
net.ipv4.tcp_fin_timeout = 1
 

然後執行以下命令過載配置

 sysctl -p