ction.c(28): Error -27796: Failed to connect to server "xxxx": [10060] Connection timed out

100并发 压测 后台web管理系统 查询用户反馈记录，报错Action.c(28): Error -27796: Failed to connect to server "xxxx": [10060] Connection timed out，错误率超过0.1%

排查：/var/log路径 命令 tailf messages,看到网卡丢包的问题

日志：

ar  4 10:38:29 localhost kernel: __ratelimit: 38 callbacks suppressed

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:29 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:34 localhost kernel: __ratelimit: 193 callbacks suppressed

Mar  4 10:38:34 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:34 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:35 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:35 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:35 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:35 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:35 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:36 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:36 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:36 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:40 localhost kernel: __ratelimit: 93 callbacks suppressed

Mar  4 10:38:40 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:41 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:41 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:42 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:42 localhost kernel: nf_conntrack: table full, dropping packet.

Mar  4 10:38:42 localhost kernel: nf_conntrack: table full, dropping packet.

原因

服务器访问量大，内核netfilter模块conntrack相关参数配置不合理，导致新连接被drop掉。

解决：

关闭linux服务器防火墙

命令：

1. 永久性生效

开启：chkconfig iptables on

关闭：chkconfig iptables off

2. 即时生效，重启后失效

开启：service iptables start

关闭：service iptables stop