# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1

# me write param
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_tw_reuse=1
net.ipv4.tcp_tw_recycle=1
net.ipv4.tcp_fin_timeout=30
#net.ipv4.tcp_window_scaling = 0

net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_orphan_retries=3
#net.ipv4.tcp_syn_retries=2
#net.ipv4.tcp_max_syn_backlog = 20480
#net.ipv4.tcp_max_tw_buckets = 20000
net.ipv4.ip_local_port_range = 10240 65000 #端口范围
#net.ipv4.tcp_keepalive_probes=5
#net.ipv4.tcp_timestamps=0

# me
#net.core.netdev_max_backlog = 32768
#net.ipv4.netfilter.ip_conntrack_max = 655360
#net.ipv4.netfilter.ip_conntrack_tcp_timeout_established = 180

linux的sysctl基本配置