I get this error message(centos 6):
Jun 12 07:42:40 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 08:07:05 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 08:27:37 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 08:42:29 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 08:48:53 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 08:51:17 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 08:55:26 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
Jun 12 09:05:24 localhost kernel: possible SYN flooding on port 8222. Sending cookies.
I have read this article,and this one, I have change it like this:
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
net.ipv4.tcp_syncookies = 1
error: "net.bridge.bridge-nf-call-ip6tables" is an unknown key
error: "net.bridge.bridge-nf-call-iptables" is an unknown key
error: "net.bridge.bridge-nf-call-arptables" is an unknown key
kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
net.nf_conntrack_max = 2097152
net.netfilter.nf_conntrack_tcp_timeout_established = 300
net.netfilter.nf_conntrack_max = 1048576
net.netfilter.nf_conntrack_tcp_timeout_close_wait = 60
net.netfilter.nf_conntrack_tcp_timeout_fin_wait = 120
net.netfilter.nf_conntrack_tcp_timeout_time_wait = 120
net.ipv4.conf.default.forwarding = 1
net.ipv4.tcp_max_syn_backlog = 819200
net.ipv4.tcp_syn_retries = 1
But those does not work for me, still get error messages.
Also, I have check my nginx settings:
worker_processes 2;
worker_cpu_affinity 0001 0010 0100 1000;
worker_rlimit_nofile 655350;
error_log logs/error.log;
#error_log logs/error.log notice;
#error_log logs/error.log info;
and the nginx error message like this:
2018/06/12 16:46:32 [error] 98768#0: *918099510 connect() failed (110: Connection timed out) while connecting to upstream, client: 192.168.1.4, server: localhost, request: "POST /AirService HTTP/1.0", upstream: "https://216.113.xxx.88:443/B2BGateway/connect/uAPI/AirService", host: "192.168.1.2:8222"
2018/06/12 16:46:32 [error] 98766#0: *918099518 connect() failed (110: Connection timed out) while connecting to upstream, client: 192.168.1.4, server: localhost, request: "POST /AirService HTTP/1.0", upstream: "https://216.113.xxx.88:443/B2BGateway/connect/uAPI/AirService", host: "192.168.1.2:8222"
2018/06/12 16:46:32 [error] 98768#0: *918099512 connect() failed (110: Connection timed out) while connecting to upstream, client: 192.168.1.4, server: localhost, request: "POST /AirService HTTP/1.0", upstream: "https://216.113.xxx.88:443/B2BGateway/connect/uAPI/AirService", host: "192.168.1.2:8222"
2018/06/12 16:46:32 [error] 98768#0: *918099513 connect() failed (110: Connection timed out) while connecting to upstream, client: 192.168.1.4, server: localhost, request: "POST /AirService HTTP/1.0", upstream: "https://216.113.xxx.88:443/B2BGateway/connect/uAPI/AirService", host: "192.168.1.2:8222"
2018/06/12 16:46:32 [error] 98767#0: *918099520 connect() failed (110: Connection timed out) while connecting to upstream, client: 192.168.1.4, server: localhost, request: "POST /AirService HTTP/1.0", upstream: "https://216.113.xxx.88:443/B2BGateway/connect/uAPI/AirService", host: "192.168.1.2:8222"
Please give me some help, thanks.