fix bug

lemp.sh

@@ -61,6 +61,7 @@ net.ipv4.tcp_max_tw_buckets = 20000
 net.ipv4.route.gc_timeout = 100
 net.ipv4.tcp_syn_retries = 1
 net.ipv4.tcp_synack_retries = 1
+net.ipv4.tcp_syncookies = 1
 net.core.somaxconn = 65535
 net.core.netdev_max_backlog = 262144
 net.ipv4.tcp_timestamps = 0