{"id":351,"date":"2023-11-26T21:13:44","date_gmt":"2023-11-26T13:13:44","guid":{"rendered":"http:\/\/8.141.4.74\/?p=351"},"modified":"2024-03-28T13:42:48","modified_gmt":"2024-03-28T05:42:48","slug":"tcp%e5%86%85%e6%a0%b8%e5%8f%82%e6%95%b0","status":"publish","type":"post","link":"http:\/\/8.141.4.74\/?p=351","title":{"rendered":"TCP\u5185\u6838\u53c2\u6570"},"content":{"rendered":"

TCP\u5185\u6838\u53c2\u6570<\/h1>\n

1.\u4fee\u6539TCP\u5185\u6838\u53c2\u6570<\/h2>\n

systcl.conf<\/h3>\n
\n

\u5728Linux\u7cfb\u7edf\u4e2d\uff0c\/proc\/sys\/net\/ipv4\/tcp_max_syn_backlog<\/code>\u6587\u4ef6\u3001\/proc\/sys\/net\/core\/somaxconn<\/code>\u6587\u4ef6\u548c\/etc\/sysctl.conf<\/code>\u6587\u4ef6\u90fd\u4e0e\u7cfb\u7edf\u5185\u6838\u53c2\u6570\u6709\u5173\u3002\u5b83\u4eec\u4e4b\u95f4\u7684\u533a\u522b\u4e3b\u8981\u5728\u4e8e\u751f\u6548\u65f6\u95f4\u548c\u6301\u4e45\u6027\u3002\u76f4\u63a5\u4fee\u6539\/proc\/sys\/net\/ipv4\/tcp_max_syn_backlog<\/code>\u6587\u4ef6\u4f1a\u7acb\u5373\u751f\u6548\uff0c\u4f46\u91cd\u542f\u540e\u66f4\u6539\u4f1a\u4e22\u5931\uff1b\u800c\u4fee\u6539\/etc\/sysctl.conf<\/code>\u6587\u4ef6\u53ef\u4ee5\u4f7f\u66f4\u6539\u5728\u7cfb\u7edf\u91cd\u542f\u540e\u4f9d\u7136\u751f\u6548\u3002<\/p>\n<\/blockquote>\n

#\u9996\u5148\uff0c\u5173\u4e8e\u9ed8\u8ba4\u503c\uff1anet.ipv4.tcp_max_syn_backlog\u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a128\uff0c\u800cnet.core.somaxconn\u7684\u9ed8\u8ba4\u503c\u56e0Linux\u53d1\u884c\u7248\u800c\u5f02\uff0c\u901a\u5e38\u4e3a128\u6216512\u3002\u8981\u67e5\u770b\u5f53\u524d\u503c\uff0c\u8bf7\u6267\u884c\u4ee5\u4e0b\u547d\u4ee4\uff1a\n[root@CentOS8 ~]# vim \/proc\/sys\/net\/core\/somaxconn\n[root@CentOS8 ~]# sysctl net.ipv4.tcp_max_syn_backlog\nnet.ipv4.tcp_max_syn_backlog = 128\n[root@CentOS8 ~]# sysctl net.core.somaxconn\nnet.core.somaxconn = 128\n[root@CentOS8 ~]#\n\n1.#\u4fee\u6539\/proc\/sys\/net\/ipv4\/tcp_max_syn_backlog\u7684\u503c\uff0c\u4ee5\u589e\u52a0\u7cfb\u7edf\u5141\u8bb8\u7684\u534a\u8fde\u63a5\u961f\u5217\u5927\u5c0f\u3002\u8981\u5b9e\u73b0\u8fd9\u4e00\u76ee\u6807\uff0c\u4f7f\u7528sysctl\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_max_syn_backlog=1024\n#\u4f7f\u7528sysctl -w\u547d\u4ee4\u4fee\u6539\u7684\u53c2\u6570\u503c\u4ec5\u5728\u5f53\u524d\u7cfb\u7edf\u8fd0\u884c\u671f\u95f4\u6709\u6548\uff0c\u7cfb\u7edf\u91cd\u542f\u540e\u5c06\u6062\u590d\u4e3a\u9ed8\u8ba4\u503c\u6216\/etc\/sysctl.conf\u4e2d\u7684\u8bbe\u7f6e\u3002\n#\u8fd9\u6761\u547d\u4ee4\u4f1a\u4e34\u65f6\u5730\u4fee\u6539tcp_max_syn_backlog\u7684\u503c\u3002\u8981\u4f7f\u8be5\u8bbe\u7f6e\u5728\u7cfb\u7edf\u91cd\u542f\u540e\u4f9d\u7136\u751f\u6548\uff0c\u9700\u8981\u7f16\u8f91\/etc\/sysctl.conf\u6587\u4ef6\u3002\u4f7f\u7528\u6587\u672c\u7f16\u8f91\u5668\uff08\u5982nano\u6216vi\uff09\u6253\u5f00\u6b64\u6587\u4ef6\uff0c\u5e76\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_max_syn_backlog = 1024\n#\u4fdd\u5b58\u5e76\u5173\u95ed\u6587\u4ef6\u3002\u63a5\u4e0b\u6765\uff0c\u8fd0\u884c\u4ee5\u4e0b\u547d\u4ee4\u4f7f\u4fee\u6539\u751f\u6548\uff1a\nsudo sysctl -p\n#\u73b0\u5728\uff0ctcp_max_syn_backlog\u7684\u503c\u5df2\u6210\u529f\u66f4\u6539\u4e3a1024\uff0c\u4e14\u5728\u7cfb\u7edf\u91cd\u542f\u540e\u4ecd\u7136\u751f\u6548\u3002\n\n2.#\u4fee\u6539\/proc\/sys\/net\/core\/somaxconn\u7684\u503c\uff0c\u4ee5\u589e\u52a0\u7cfb\u7edf\u5141\u8bb8\u7684\u5168\u8fde\u63a5\u961f\u5217\u5927\u5c0f\u3002\u8981\u5b9e\u73b0\u8fd9\u4e00\u76ee\u6807\uff0c\u4f7f\u7528sysctl\u547d\u4ee4\uff1a\nsudo sysctl -w net.core.somaxconn = 1024\n\n#\u4e3a\u4e86\u4f7f\u66f4\u6539\u5728\u7cfb\u7edf\u91cd\u542f\u540e\u4f9d\u7136\u751f\u6548\uff0c\u5728\/etc\/sysctl.conf\u6587\u4ef6\u4e2d\u4fee\u6539\u76f8\u5e94\u7684\u53c2\u6570\u3002\u5c06\u4ee5\u4e0b\u5185\u5bb9\u6dfb\u52a0\u5230\/etc\/sysctl.conf\u6587\u4ef6\u4e2d\nnet.core.somaxconn = 1024\n#\u4fdd\u5b58\u5e76\u5173\u95ed\u6587\u4ef6\u3002\u63a5\u4e0b\u6765\uff0c\u8fd0\u884c\u4ee5\u4e0b\u547d\u4ee4\u4f7f\u4fee\u6539\u751f\u6548\uff1a\nsudo sysctl -p\n#\u73b0\u5728\uff0cnet.core.somaxconn\u53c2\u6570\u7684\u503c\u5df2\u6210\u529f\u66f4\u6539\uff0c\u5e76\u4e14\u5728\u7cfb\u7edf\u91cd\u542f\u540e\u4ecd\u7136\u751f\u6548\u3002<\/code><\/pre>\n
syn\u534a\u8fde\u63a5\u961f\u5217\u548caccept\u5168\u8fde\u63a5\u961f\u5217<\/h3>\n
\n
\u5728TCP\uff08\u4f20\u8f93\u63a7\u5236\u534f\u8bae\uff09\u4e2d\uff0c\u5f53\u5ba2\u6237\u7aef\u4e0e\u670d\u52a1\u5668\u4e4b\u95f4\u5efa\u7acb\u8fde\u63a5\u65f6\uff0c\u4f1a\u4f7f\u7528\u4e09\u6b21\u63e1\u624b\uff08Three-Way Handshake\uff09\u534f\u8bae\u3002\u5728\u8fd9\u4e2a\u8fc7\u7a0b\u4e2d\uff0c\u670d\u52a1\u5668\u9700\u8981\u5904\u7406\u4e24\u79cd\u7c7b\u578b\u7684\u8fde\u63a5\u961f\u5217\uff1aSYN\u534a\u8fde\u63a5\u961f\u5217\u548cAccept\u5168\u8fde\u63a5\u961f\u5217\u3002<\/p>\n<\/blockquote>\n
    \n
  1. SYN\u534a\u8fde\u63a5\u961f\u5217\uff1a<\/li>\n<\/ol>\n
    \u5728TCP\u8fde\u63a5\u5efa\u7acb\u8fc7\u7a0b\u7684\u7b2c\u4e00\u6b65\uff0c\u5ba2\u6237\u7aef\u4f1a\u53d1\u9001\u4e00\u4e2a\u5e26\u6709SYN\uff08synchronize\uff09\u6807\u5fd7\u4f4d\u7684\u6570\u636e\u5305\u7ed9\u670d\u52a1\u5668\uff0c\u8bf7\u6c42\u5efa\u7acb\u8fde\u63a5\u3002\u670d\u52a1\u5668\u6536\u5230\u8fd9\u4e2aSYN\u5305\u540e\uff0c\u4f1a\u5c06\u6b64\u8fde\u63a5\u653e\u5165SYN\u534a\u8fde\u63a5\u961f\u5217\u3002\u6b64\u65f6\uff0c\u8fde\u63a5\u8fd8\u6ca1\u6709\u5b8c\u5168\u5efa\u7acb\uff0c\u670d\u52a1\u5668\u4ec5\u6536\u5230\u4e86\u5ba2\u6237\u7aef\u7684\u8fde\u63a5\u8bf7\u6c42\u3002\nSYN\u534a\u8fde\u63a5\u961f\u5217\u4e3b\u8981\u7528\u4e8e\u5b58\u50a8\u5904\u4e8eSYN_RECV\u72b6\u6001\u7684\u8fde\u63a5\u3002\u8fd9\u4e9b\u8fde\u63a5\u5df2\u7ecf\u63a5\u6536\u5230\u5ba2\u6237\u7aef\u7684SYN\u5305\uff0c\u4f46\u5c1a\u672a\u5b8c\u6210\u6574\u4e2a\u4e09\u6b21\u63e1\u624b\u8fc7\u7a0b\u3002SYN\u534a\u8fde\u63a5\u961f\u5217\u7684\u957f\u5ea6\u7531`net.ipv4.tcp_max_syn_backlog`\u5185\u6838\u53c2\u6570\u63a7\u5236\u3002\u5f53SYN\u534a\u8fde\u63a5\u961f\u5217\u6ee1\u65f6\uff0c\u670d\u52a1\u5668\u53ef\u80fd\u4f1a\u62d2\u7edd\u65b0\u7684\u8fde\u63a5\u8bf7\u6c42\u3002<\/code><\/pre>\n
      \n
    1. Accept\u5168\u8fde\u63a5\u961f\u5217\uff1a<\/li>\n<\/ol>\n
      \u5f53\u670d\u52a1\u5668\u6536\u5230\u5ba2\u6237\u7aef\u7684SYN\u5305\u540e\uff0c\u5b83\u4f1a\u53d1\u9001\u4e00\u4e2a\u5e26\u6709SYN\u548cACK\uff08acknowledge\uff09\u6807\u5fd7\u4f4d\u7684\u6570\u636e\u5305\u7ed9\u5ba2\u6237\u7aef\uff0c\u786e\u8ba4\u6536\u5230\u4e86\u8fde\u63a5\u8bf7\u6c42\u3002\u7136\u540e\uff0c\u5ba2\u6237\u7aef\u56de\u5e94\u4e00\u4e2aACK\u5305\u7ed9\u670d\u52a1\u5668\uff0c\u8868\u793a\u8fde\u63a5\u5df2\u7ecf\u5efa\u7acb\u3002\u6b64\u65f6\uff0c\u670d\u52a1\u5668\u4f1a\u5c06\u8be5\u8fde\u63a5\u4eceSYN\u534a\u8fde\u63a5\u961f\u5217\u79fb\u52a8\u5230Accept\u5168\u8fde\u63a5\u961f\u5217\u3002\nAccept\u5168\u8fde\u63a5\u961f\u5217\u5b58\u50a8\u5904\u4e8eESTABLISHED\u72b6\u6001\u7684\u8fde\u63a5\uff0c\u8fd9\u4e9b\u8fde\u63a5\u5df2\u7ecf\u5b8c\u6210\u4e86\u4e09\u6b21\u63e1\u624b\u8fc7\u7a0b\u3002Accept\u5168\u8fde\u63a5\u961f\u5217\u7684\u957f\u5ea6\u7531net.core.somaxconn\u5185\u6838\u53c2\u6570\u63a7\u5236\u3002\u5f53Accept\u5168\u8fde\u63a5\u961f\u5217\u6ee1\u65f6\uff0c\u670d\u52a1\u5668\u53ef\u80fd\u65e0\u6cd5\u5904\u7406\u66f4\u591a\u7684\u5e76\u53d1\u8fde\u63a5\u3002<\/code><\/pre>\n
      \u670d\u52a1\u5668\u5e94\u7528\u7a0b\u5e8f\uff08\u5982Web\u670d\u52a1\u5668\uff09\u9700\u8981\u5728\u5408\u9002\u7684\u65f6\u95f4\u5185\u63a5\u53d7\uff08accept\uff09\u5168\u8fde\u63a5\u961f\u5217\u4e2d\u7684\u8fde\u63a5\uff0c\u4ee5\u4fbf\u4e3a\u5ba2\u6237\u7aef\u63d0\u4f9b\u670d\u52a1\u3002\u5982\u679c\u670d\u52a1\u5668\u5e94\u7528\u7a0b\u5e8f\u5904\u7406\u8fde\u63a5\u7684\u901f\u5ea6\u4e0d\u591f\u5feb\uff0c\u5168\u8fde\u63a5\u961f\u5217\u53ef\u80fd\u4f1a\u53d8\u6ee1\uff0c\u5bfc\u81f4\u65b0\u7684\u8fde\u63a5\u88ab\u62d2\u7edd\u3002<\/p>\n
      \u603b\u4e4b\uff0cSYN\u534a\u8fde\u63a5\u961f\u5217\u548cAccept\u5168\u8fde\u63a5\u961f\u5217\u662f\u670d\u52a1\u5668\u5728TCP\u8fde\u63a5\u5efa\u7acb\u8fc7\u7a0b\u4e2d\u4f7f\u7528\u7684\u4e24\u79cd\u7c7b\u578b\u7684\u961f\u5217\u3002SYN\u534a\u8fde\u63a5\u961f\u5217\u7528\u4e8e\u5b58\u50a8\u5c1a\u672a\u5b8c\u6210\u4e09\u6b21\u63e1\u624b\u7684\u8fde\u63a5\uff0c\u800cAccept\u5168\u8fde\u63a5\u961f\u5217\u7528\u4e8e\u5b58\u50a8\u5df2\u7ecf\u5efa\u7acb\u7684\u8fde\u63a5\u3002\u901a\u8fc7\u4f18\u5316\u8fd9\u4e24\u4e2a\u961f\u5217\u7684\u957f\u5ea6\u548c\u670d\u52a1\u5668\u5e94\u7528\u7a0b\u5e8f\u7684\u5904\u7406\u901f\u5ea6\uff0c\u53ef\u4ee5\u63d0\u9ad8\u670d\u52a1\u5668\u7684\u5e76\u53d1\u8fde\u63a5\u5904\u7406\u80fd\u529b<\/p>\n
      2.TCP\u5185\u6838\u53c2\u6570<\/h2>\n
      #net.ipv4.tcp_max_syn_backlog: \u63a7\u5236SYN\u534a\u8fde\u63a5\u961f\u5217\u7684\u5927\u5c0f\u3002\u63a8\u8350\u503c\uff1a1024\u6216\u66f4\u5927\uff0c\u6839\u636e\u5e76\u53d1\u8fde\u63a5\u9700\u6c42\u8fdb\u884c\u8c03\u6574\u3002\n#net.core.somaxconn: \u63a7\u5236Accept\u5168\u8fde\u63a5\u961f\u5217\u7684\u5927\u5c0f\u3002\u63a8\u8350\u503c\uff1a1024\u6216\u66f4\u5927\uff0c\u6839\u636e\u5e76\u53d1\u8fde\u63a5\u9700\u6c42\u8fdb\u884c\u8c03\u6574\u3002\n#net.ipv4.tcp_tw_reuse: \u63a7\u5236\u662f\u5426\u5141\u8bb8\u91cd\u7528\u5904\u4e8eTIME_WAIT\u72b6\u6001\u7684\u5957\u63a5\u5b57\u3002\u63a8\u8350\u503c\uff1a1\uff08\u542f\u7528\uff09\u3002\n#net.ipv4.tcp_tw_recycle: \u63a7\u5236\u662f\u5426\u66f4\u5feb\u5730\u56de\u6536\u5904\u4e8eTIME_WAIT\u72b6\u6001\u7684\u5957\u63a5\u5b57\u3002\u63a8\u8350\u503c\uff1a0\uff08\u7981\u7528\uff09\uff0c\u56e0\u4e3a\u5b83\u53ef\u80fd\u5728NAT\u73af\u5883\u4e0b\u5bfc\u81f4\u8fde\u63a5\u95ee\u9898\u3002\n#net.ipv4.tcp_fin_timeout: \u63a7\u5236\u5957\u63a5\u5b57\u5728FIN_WAIT_2\u72b6\u6001\u4e0b\u7b49\u5f85\u5173\u95ed\u7684\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\u3002\u63a8\u8350\u503c\uff1a30-60\u3002\n#net.ipv4.tcp_keepalive_time: \u63a7\u5236TCP keep-alive\u6d88\u606f\u53d1\u9001\u7684\u95f4\u9694\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\u3002\u63a8\u8350\u503c\uff1a600\u3002\n#net.ipv4.tcp_keepalive_probes: \u63a7\u5236\u5728\u8ba4\u4e3a\u8fde\u63a5\u5df2\u65ad\u5f00\u4e4b\u524d\u53d1\u9001TCP keep-alive\u6d88\u606f\u7684\u6b21\u6570\u3002\u63a8\u8350\u503c\uff1a9\u3002\n#net.ipv4.tcp_keepalive_intvl: \u63a7\u5236\u8fde\u7eedTCP keep-alive\u6d88\u606f\u4e4b\u95f4\u7684\u65f6\u95f4\u95f4\u9694\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\u3002\u63a8\u8350\u503c\uff1a75\u3002\n#net.ipv4.tcp_synack_retries: \u63a7\u5236TCP SYN+ACK\u91cd\u8bd5\u7684\u6b21\u6570\u3002\u63a8\u8350\u503c\uff1a5\u3002\n#net.ipv4.tcp_syn_retries: \u63a7\u5236TCP SYN\u91cd\u8bd5\u7684\u6b21\u6570\u3002\u63a8\u8350\u503c\uff1a5\u3002\n\n#vim \/etc\/sysctl.conf\n# SYN\u534a\u8fde\u63a5\u961f\u5217\u5927\u5c0f\nnet.ipv4.tcp_max_syn_backlog = 1024\n# Accept\u5168\u8fde\u63a5\u961f\u5217\u5927\u5c0f\nnet.core.somaxconn = 1024\n# \u5141\u8bb8\u91cd\u7528TIME_WAIT\u72b6\u6001\u7684\u5957\u63a5\u5b57\nnet.ipv4.tcp_tw_reuse = 1\n# \u7981\u6b62\u66f4\u5feb\u5730\u56de\u6536TIME_WAIT\u72b6\u6001\u7684\u5957\u63a5\u5b57\nnet.ipv4.tcp_tw_recycle = 0\n# \u5957\u63a5\u5b57\u5728FIN_WAIT_2\u72b6\u6001\u4e0b\u7b49\u5f85\u5173\u95ed\u7684\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\nnet.ipv4.tcp_fin_timeout = 30\n# TCP keep-alive\u6d88\u606f\u53d1\u9001\u7684\u95f4\u9694\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\nnet.ipv4.tcp_keepalive_time = 600\n# \u5728\u8ba4\u4e3a\u8fde\u63a5\u5df2\u65ad\u5f00\u4e4b\u524d\u53d1\u9001TCP keep-alive\u6d88\u606f\u7684\u6b21\u6570\nnet.ipv4.tcp_keepalive_probes = 9\n# \u8fde\u7eedTCP keep-alive\u6d88\u606f\u4e4b\u95f4\u7684\u65f6\u95f4\u95f4\u9694\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\nnet.ipv4.tcp_keepalive_intvl = 75\n# TCP SYN+ACK\u91cd\u8bd5\u7684\u6b21\u6570\nnet.ipv4.tcp_synack_retries = 5\n# TCP SYN\u91cd\u8bd5\u7684\u6b21\u6570\nnet.ipv4.tcp_syn_retries = 5<\/code><\/pre>\n
      \u2474 net.core.somaxconn<\/h3>\n
      \u4fee\u6539net.core.somaxconn<\/code>\u53c2\u6570\u7684\u4e3b\u8981\u7528\u9014\u662f\u8c03\u6574\u670d\u52a1\u5668\u7684Accept\u5168\u8fde\u63a5\u961f\u5217\u7684\u6700\u5927\u957f\u5ea6\u3002Accept\u5168\u8fde\u63a5\u961f\u5217\u5b58\u50a8\u5904\u4e8eESTABLISHED\u72b6\u6001\u7684\u8fde\u63a5\uff0c\u8fd9\u4e9b\u8fde\u63a5\u5df2\u7ecf\u5b8c\u6210\u4e86TCP\u4e09\u6b21\u63e1\u624b\u8fc7\u7a0b\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/core\/somaxconn<\/p>\n
      \u589e\u52a0net.core.somaxconn<\/code>\u503c\u53ef\u4ee5\u63d0\u9ad8\u670d\u52a1\u5668\u5728\u7e41\u5fd9\u65f6\u6bb5\u5904\u7406\u5e76\u53d1\u8fde\u63a5\u7684\u80fd\u529b\u3002\u5f53\u670d\u52a1\u5668\u63a5\u6536\u5230\u5927\u91cf\u7684\u5e76\u53d1\u8fde\u63a5\u8bf7\u6c42\u65f6\uff0c\u8f83\u5927\u7684net.core.somaxconn<\/code>\u503c\u6709\u52a9\u4e8e\u786e\u4fdd\u670d\u52a1\u5668\u80fd\u591f\u5bb9\u7eb3\u66f4\u591a\u7684\u5df2\u5efa\u7acb\u8fde\u63a5\u3002\u8fd9\u6709\u52a9\u4e8e\u51cf\u5c11\u56e0\u4e3a\u5168\u8fde\u63a5\u961f\u5217\u5df2\u6ee1\u5bfc\u81f4\u7684\u8fde\u63a5\u8bf7\u6c42\u88ab\u62d2\u7edd\u7684\u60c5\u51b5\u3002<\/p>\n
      \u7136\u800c\uff0c\u589e\u52a0net.core.somaxconn<\/code>\u503c\u5e76\u4e0d\u80fd\u76f4\u63a5\u63d0\u9ad8\u670d\u52a1\u5668\u7684\u6027\u80fd\u3002\u5b9e\u9645\u4e0a\uff0c\u5982\u679c\u670d\u52a1\u5668\u7684\u5904\u7406\u80fd\u529b\u6709\u9650\uff0c\u8bbe\u7f6e\u8fc7\u9ad8\u7684net.core.somaxconn<\/code>\u503c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u670d\u52a1\u5668\u8d44\u6e90\u4e0d\u8db3\u4ee5\u5904\u7406\u6240\u6709\u7684\u8fde\u63a5\uff0c\u4ece\u800c\u5f71\u54cd\u6574\u4f53\u6027\u80fd\u3002\u56e0\u6b64\uff0c\u5728\u8c03\u6574net.core.somaxconn<\/code>\u503c\u65f6\uff0c\u9700\u8981\u6743\u8861\u670d\u52a1\u5668\u7684\u5b9e\u9645\u9700\u6c42\u548c\u6027\u80fd\u3002<\/p>\n
      \u603b\u4e4b\uff0c\u4fee\u6539net.core.somaxconn<\/code>\u53c2\u6570\u53ef\u4ee5\u8c03\u6574\u670d\u52a1\u5668\u7684Accept\u5168\u8fde\u63a5\u961f\u5217\u957f\u5ea6\uff0c\u4ece\u800c\u5f71\u54cd\u670d\u52a1\u5668\u5904\u7406\u5e76\u53d1\u8fde\u63a5\u7684\u80fd\u529b\u3002\u5728\u8c03\u6574\u6b64\u53c2\u6570\u65f6\uff0c\u5e94\u6839\u636e\u670d\u52a1\u5668\u7684\u5b9e\u9645\u9700\u6c42\u548c\u6027\u80fd\u8fdb\u884c\u5408\u7406\u914d\u7f6e\u3002<\/p>\n
      sudo sysctl -w net.core.somaxconn=1024<\/code><\/pre>\n
      \u2475net.ipv4.tcp_max_syn_backlog<\/h3>\n
      net.ipv4.tcp_max_syn_backlog<\/code>\u662f\u4e00\u4e2aLinux\u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u63a7\u5236SYN\u534a\u8fde\u63a5\u961f\u5217\u7684\u6700\u5927\u957f\u5ea6\u3002\u534a\u8fde\u63a5\u961f\u5217\u7528\u4e8e\u5b58\u50a8\u5df2\u6536\u5230SYN\u5305\u4f46\u5c1a\u672a\u5b8c\u6210TCP\u4e09\u6b21\u63e1\u624b\u7684\u8fde\u63a5\u8bf7\u6c42\u3002\u5f53\u5ba2\u6237\u7aef\u5411\u670d\u52a1\u5668\u53d1\u9001SYN\u5305\uff08\u7b2c\u4e00\u6b21\u63e1\u624b\uff09\u65f6\uff0c\u670d\u52a1\u5668\u5c06\u8fd9\u4e2a\u8fde\u63a5\u8bf7\u6c42\u653e\u5165SYN\u534a\u8fde\u63a5\u961f\u5217\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/core\/netdev_max_backlog<\/p>\n
      \u6b64\u53c2\u6570\u5bf9\u670d\u52a1\u5668\u7684\u6027\u80fd\u548c\u5e76\u53d1\u8fde\u63a5\u5904\u7406\u80fd\u529b\u6709\u5f71\u54cd\u3002\u5728\u670d\u52a1\u5668\u9762\u4e34\u5927\u91cf\u5e76\u53d1\u8fde\u63a5\u8bf7\u6c42\u65f6\uff0c\u8f83\u5927\u7684net.ipv4.tcp_max_syn_backlog<\/code>\u503c\u6709\u52a9\u4e8e\u51cf\u5c11\u56e0SYN\u534a\u8fde\u63a5\u961f\u5217\u5df2\u6ee1\u800c\u5bfc\u81f4\u7684\u65b0\u8fde\u63a5\u8bf7\u6c42\u88ab\u62d2\u7edd\u7684\u60c5\u51b5\u3002\u7136\u800c\uff0c\u8bbe\u7f6e\u8fc7\u9ad8\u7684\u503c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u670d\u52a1\u5668\u8d44\u6e90\u4e0d\u8db3\u4ee5\u5904\u7406\u6240\u6709\u8fde\u63a5\uff0c\u4ece\u800c\u5f71\u54cd\u6574\u4f53\u6027\u80fd\u3002<\/p>\n
      net.ipv4.tcp_max_syn_backlog<\/code>\u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a128\uff0c\u4f46\u60a8\u53ef\u4ee5\u6839\u636e\u670d\u52a1\u5668\u7684\u5b9e\u9645\u9700\u6c42\u548c\u6027\u80fd\u8c03\u6574\u6b64\u503c\u3002\u8981\u4fee\u6539net.ipv4.tcp_max_syn_backlog<\/code>\uff0c\u60a8\u53ef\u4ee5\u4f7f\u7528sysctl<\/code>\u547d\u4ee4\u6216\u7f16\u8f91\/etc\/sysctl.conf<\/code>\u6587\u4ef6\u3002\u4f8b\u5982\uff0c\u8981\u5c06net.ipv4.tcp_max_syn_backlog<\/code>\u7684\u503c\u8bbe\u7f6e\u4e3a1024\uff0c\u60a8\u53ef\u4ee5\u6267\u884c\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
      sudo sysctl -w net.ipv4.tcp_max_syn_backlog=1024<\/code><\/pre>\n
      \u8bf7\u6ce8\u610f\uff0c\u4f7f\u7528sysctl -w<\/code>\u547d\u4ee4\u4fee\u6539\u7684\u53c2\u6570\u503c\u4ec5\u5728\u5f53\u524d\u7cfb\u7edf\u8fd0\u884c\u671f\u95f4\u6709\u6548\u3002\u7cfb\u7edf\u91cd\u542f\u540e\uff0c\u53c2\u6570\u503c\u5c06\u6062\u590d\u4e3a\u9ed8\u8ba4\u503c\u6216\/etc\/sysctl.conf<\/code>\u4e2d\u7684\u8bbe\u7f6e\u3002\u8981\u4f7f\u66f4\u6539\u5728\u7cfb\u7edf\u91cd\u542f\u540e\u4f9d\u7136\u751f\u6548\uff0c\u8bf7\u5c06\u4ee5\u4e0b\u5185\u5bb9\u6dfb\u52a0\u5230\/etc\/sysctl.conf<\/code>\u6587\u4ef6\u4e2d\uff1a<\/p>\n
      net.ipv4.tcp_max_syn_backlog = 1024<\/code><\/pre>\n
      \u7136\u540e\u8fd0\u884c\u4ee5\u4e0b\u547d\u4ee4\u4ee5\u4f7f\u66f4\u6539\u751f\u6548\uff1a<\/p>\n
      sudo sysctl -p<\/code><\/pre>\n
      \u2476 net.ipv4.tcp_fin_timeout<\/h3>\n
      net.ipv4.tcp_fin_timeout<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e\u5185\u6838\u5728 FIN_WAIT_2 \u72b6\u6001\u4e0b\u5173\u95ed TCP \u8fde\u63a5\u4e4b\u524d\u5e94\u7b49\u5f85\u7684\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09,\u8fd9\u4e2a\u53c2\u6570\u53ef\u4ee5\u5f71\u54cd\u5230\u5173\u95ed\u8fde\u63a5\u7684\u901f\u5ea6\u3002FIN_WAIT_2 \u72b6\u6001\u662f TCP \u8fde\u63a5\u7ec8\u6b62\u8fc7\u7a0b\u7684\u4e00\u90e8\u5206\uff0c\u5728\u8be5\u8fc7\u7a0b\u4e2d\uff0c\u8fde\u63a5\u7684\u53cc\u65b9\u4ea4\u6362 FIN\uff08\u7ed3\u675f\uff09\u6570\u636e\u5305\u4ee5\u8868\u793a\u5b83\u4eec\u5df2\u5b8c\u6210\u6570\u636e\u53d1\u9001\u5e76\u51c6\u5907\u5173\u95ed\u8fde\u63a5\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/ipv4\/tcp_fin_timeout<\/p>\n
      net.ipv4.tcp_fin_timeout<\/code> \u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 60 \u79d2\uff0c\u8fd9\u610f\u5473\u7740\u5728 FIN_WAIT_2 \u72b6\u6001\u4e0b\uff0c\u8fde\u63a5\u5728\u5173\u95ed\u524d\u5c06\u7b49\u5f85 60 \u79d2\u3002\u8fd9\u4e2a\u53c2\u6570\u53ef\u4ee5\u6839\u636e\u5b9e\u9645\u9700\u6c42\u8fdb\u884c\u8c03\u6574\u3002\u8f83\u77ed\u7684\u8d85\u65f6\u65f6\u95f4\u53ef\u4ee5\u4f7f\u7cfb\u7edf\u66f4\u5feb\u5730\u91ca\u653e\u4e0d\u518d\u4f7f\u7528\u7684\u8fde\u63a5\u8d44\u6e90\uff0c\u4ece\u800c\u63d0\u9ad8\u7cfb\u7edf\u6027\u80fd\u3002\u7136\u800c\uff0c\u5c06\u6b64\u503c\u8bbe\u7f6e\u5f97\u8fc7\u4f4e\u53ef\u80fd\u5bfc\u81f4\u7f51\u7edc\u8fde\u63a5\u8fc7\u65e9\u5173\u95ed\uff0c\u8fdb\u800c\u5f71\u54cd\u5e94\u7528\u7a0b\u5e8f\u7684\u6b63\u5e38\u5de5\u4f5c\u3002<\/p>\n
      \u8981\u67e5\u770b net.ipv4.tcp_fin_timeout<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
      sysctl net.ipv4.tcp_fin_timeout<\/code><\/pre>\n
      \u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u5176\u66f4\u6539\u4e3a 30 \u79d2\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
      sudo sysctl -w net.ipv4.tcp_fin_timeout=30<\/code><\/pre>\n
      \u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf<\/code> \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a<\/p>\n
      net.ipv4.tcp_fin_timeout = 30\n#\u751f\u6548\nsysctl -p<\/code><\/pre>\n
      \u2477 net.ipv4.tcp_tw_reuse<\/h3>\n
      net.ipv4.tcp_tw_reuse<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u63a7\u5236\u662f\u5426\u5141\u8bb8\u91cd\u7528 TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\u4ee5\u4fbf\u5feb\u901f\u56de\u6536\u3002\u8fd9\u4e2a\u8bbe\u7f6e\u5728\u9ad8\u5e76\u53d1\u3001\u5927\u91cf\u77ed\u8fde\u63a5\u573a\u666f\u4e0b\u5c24\u4e3a\u91cd\u8981\uff0c\u56e0\u4e3a\u5b83\u53ef\u4ee5\u5e2e\u52a9\u7cfb\u7edf\u66f4\u5feb\u5730\u56de\u6536\u548c\u91cd\u7528 TCP \u7aef\u53e3\u548c\u8d44\u6e90\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/ipv4\/tcp_tw_reuse\uff0c\u9ed8\u8ba4\u4e3a0<\/p>\n
      \u5728 TCP \u8fde\u63a5\u7ec8\u6b62\u8fc7\u7a0b\u4e2d\uff0c\u6709\u4e00\u4e2a\u72b6\u6001\u53eb\u505a TIME_WAIT\u3002\u5f53\u8fde\u63a5\u7ec8\u6b62\u65f6\uff0cTCP \u8fde\u63a5\u7684\u4e00\u7aef\u9700\u8981\u7b49\u5f85\u4e00\u6bb5\u65f6\u95f4\uff08\u9ed8\u8ba4\u662f 2 \u500d\u7684\u6700\u5927\u6bb5\u751f\u547d\u5468\u671f\uff0c\u7ea6\u4e3a 2 \u5206\u949f\uff09\u4ee5\u786e\u4fdd\u6240\u6709\u5728\u7f51\u7edc\u4e2d\u4f20\u8f93\u7684\u6570\u636e\u5305\u90fd\u5df2\u88ab\u63a5\u6536\u3002\u5728\u8fd9\u6bb5\u65f6\u95f4\u91cc\uff0c\u8fde\u63a5\u4f1a\u4fdd\u6301 TIME_WAIT \u72b6\u6001\u3002\u5f53\u6709\u5927\u91cf\u7684\u77ed\u8fde\u63a5\u65f6\uff0c\u5f88\u591a\u5957\u63a5\u5b57\u4f1a\u5904\u4e8e TIME_WAIT \u72b6\u6001\uff0c\u53ef\u80fd\u5bfc\u81f4\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\uff0c\u542f\u7528\u6b64\u9009\u9879\u53ef\u4ee5\u66f4\u6709\u6548\u5730\u4f7f\u7528\u7cfb\u7edf\u8d44\u6e90\u3002<\/p>\n
      net.ipv4.tcp_tw_reuse<\/code> \u7684\u53d6\u503c\u5982\u4e0b\uff1a<\/p>\n
        \n
      • 0<\/code>\uff08\u9ed8\u8ba4\u503c\uff09\uff1a\u7981\u6b62\u5957\u63a5\u5b57\u91cd\u7528\u3002\u7cfb\u7edf\u5c06\u4e25\u683c\u9075\u5faa TCP \u534f\u8bae\u89c4\u8303\uff0c\u4e0d\u5141\u8bb8\u5728 TIME_WAIT \u72b6\u6001\u4e0b\u91cd\u7528\u5957\u63a5\u5b57\u3002<\/li>\n
      • 1<\/code>\uff1a\u5141\u8bb8\u5957\u63a5\u5b57\u91cd\u7528\u3002\u7cfb\u7edf\u4f1a\u5728\u53ef\u80fd\u7684\u60c5\u51b5\u4e0b\u5c3d\u5feb\u56de\u6536\u548c\u91cd\u7528\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\uff0c\u4ece\u800c\u51cf\u8f7b\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\u7684\u95ee\u9898\u3002<\/li>\n<\/ul>\n
        \u8981\u67e5\u770b net.ipv4.tcp_tw_reuse<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
        sysctl net.ipv4.tcp_tw_reuse\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u542f\u7528\u5957\u63a5\u5b57\u91cd\u7528\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_tw_reuse=1\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_tw_reuse = 1\n#\u751f\u6548\nsysctl -p<\/code><\/pre>\n
        \u7406\u89e3\u5957\u63a5\u5b57\u91cd\u7528<\/h4>\n
        \u5957\u63a5\u5b57\u91cd\u7528\uff08socket reuse\uff09\u662f\u6307\u64cd\u4f5c\u7cfb\u7edf\u5728\u5141\u8bb8\u7684\u60c5\u51b5\u4e0b\uff0c\u66f4\u5feb\u5730\u56de\u6536\u548c\u91cd\u7528\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\u3002\u8fd9\u6709\u52a9\u4e8e\u51cf\u8f7b\u56e0\u77ed\u65f6\u95f4\u5185\u4ea7\u751f\u5927\u91cf\u77ed\u8fde\u63a5\u800c\u5bfc\u81f4\u7684\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\u95ee\u9898\u3002<\/p>\n
        \u5728 TCP \u8fde\u63a5\u7ec8\u6b62\u8fc7\u7a0b\u4e2d\uff0c\u8fde\u63a5\u7684\u4e00\u7aef\u4f1a\u8fdb\u5165 TIME_WAIT \u72b6\u6001\u3002\u8fd9\u662f\u4e3a\u4e86\u786e\u4fdd\u5728\u7f51\u7edc\u4e2d\u4f20\u8f93\u7684\u6570\u636e\u5305\u90fd\u5df2\u88ab\u63a5\u6536\u3002\u5728 TIME_WAIT \u72b6\u6001\u671f\u95f4\uff0c\u5957\u63a5\u5b57\u5360\u7528\u4e86\u7cfb\u7edf\u7684\u8d44\u6e90\uff0c\u4f8b\u5982\u7aef\u53e3\u53f7\u3002\u5f53\u6709\u5927\u91cf\u77ed\u8fde\u63a5\u65f6\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u5927\u91cf\u5957\u63a5\u5b57\u5904\u4e8e TIME_WAIT \u72b6\u6001\uff0c\u8fdb\u800c\u5bfc\u81f4\u53ef\u7528\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\u3002<\/p>\n
        \u5f53\u542f\u7528\u5957\u63a5\u5b57\u91cd\u7528\uff08\u4f8b\u5982\uff0c\u5c06 net.ipv4.tcp_tw_reuse<\/code> \u8bbe\u7f6e\u4e3a 1<\/code>\uff09\u65f6\uff0c\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u5c1d\u8bd5\u5728\u5141\u8bb8\u7684\u60c5\u51b5\u4e0b\u66f4\u5feb\u5730\u56de\u6536\u548c\u91cd\u7528\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\u3002\u8fd9\u610f\u5473\u7740\uff0c\u5c3d\u7ba1\u5957\u63a5\u5b57\u53ef\u80fd\u4ecd\u5904\u4e8e TIME_WAIT \u72b6\u6001\uff0c\u4f46\u64cd\u4f5c\u7cfb\u7edf\u53ef\u4ee5\u5c06\u5176\u5206\u914d\u7ed9\u65b0\u7684\u8fde\u63a5\uff0c\u4ece\u800c\u6709\u6548\u5730\u51cf\u8f7b\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\u95ee\u9898\u3002<\/p>\n
        \u7136\u800c\uff0c\u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u5957\u63a5\u5b57\u91cd\u7528\u53ef\u80fd\u4f1a\u5bfc\u81f4\u4e0d\u7b26\u5408 TCP \u534f\u8bae\u89c4\u8303\u7684\u884c\u4e3a\uff0c\u4f8b\u5982\u53ef\u80fd\u4ea7\u751f\u4e71\u5e8f\u7684\u6570\u636e\u5305\u3002\u56e0\u6b64\uff0c\u5728\u542f\u7528\u5957\u63a5\u5b57\u91cd\u7528\u4e4b\u524d\uff0c\u8bf7\u786e\u4fdd\u60a8\u4e86\u89e3\u53ef\u80fd\u7684\u5f71\u54cd\uff0c\u5e76\u6839\u636e\u7f51\u7edc\u73af\u5883\u548c\u5e94\u7528\u9700\u6c42\u8fdb\u884c\u6743\u8861\u3002<\/p>\n
        \u5957\u63a5\u5b57<\/h4>\n
        \u5957\u63a5\u5b57\uff08socket\uff09\u662f\u8ba1\u7b97\u673a\u7f51\u7edc\u7f16\u7a0b\u4e2d\u7684\u4e00\u4e2a\u62bd\u8c61\u6982\u5ff5\uff0c\u5b83\u662f\u7f51\u7edc\u901a\u4fe1\u7684\u57fa\u672c\u6784\u5efa\u6a21\u5757\u3002\u5957\u63a5\u5b57\u5145\u5f53\u5e94\u7528\u7a0b\u5e8f\u548c\u7f51\u7edc\u534f\u8bae\u4e4b\u95f4\u7684\u63a5\u53e3\uff0c\u4f7f\u5e94\u7528\u7a0b\u5e8f\u80fd\u591f\u4e0e\u5176\u4ed6\u5e94\u7528\u7a0b\u5e8f\u901a\u8fc7\u7f51\u7edc\u8fdb\u884c\u901a\u4fe1\u3002\u7b80\u5355\u6765\u8bf4\uff0c\u5957\u63a5\u5b57\u5c31\u50cf\u4e00\u4e2a\u7535\u8bdd\u63d2\u5ea7\uff0c\u5e94\u7528\u7a0b\u5e8f\u53ef\u4ee5\u901a\u8fc7\u5b83\u4e0e\u5176\u4ed6\u7a0b\u5e8f\u5efa\u7acb\u8fde\u63a5\u5e76\u8fdb\u884c\u901a\u4fe1\u3002<\/p>\n
        \u5728\u8ba1\u7b97\u673a\u7f51\u7edc\u4e2d\uff0c\u4e3b\u8981\u4f7f\u7528\u4e24\u79cd\u534f\u8bae\u8fdb\u884c\u901a\u4fe1\uff1aTCP\uff08\u4f20\u8f93\u63a7\u5236\u534f\u8bae\uff09\u548c UDP\uff08\u7528\u6237\u6570\u636e\u62a5\u534f\u8bae\uff09\u3002\u8fd9\u4e24\u79cd\u534f\u8bae\u90fd\u57fa\u4e8e IP\uff08\u4e92\u8054\u7f51\u534f\u8bae\uff09\uff0c\u56e0\u6b64\u901a\u5e38\u79f0\u4e3a TCP\/IP \u548c UDP\/IP\u3002\u5957\u63a5\u5b57\u53ef\u4ee5\u57fa\u4e8e\u8fd9\u4e9b\u534f\u8bae\u521b\u5efa\uff0c\u4ee5\u4fbf\u5e94\u7528\u7a0b\u5e8f\u53ef\u4ee5\u4f7f\u7528\u4e0d\u540c\u7684\u901a\u4fe1\u673a\u5236\u3002<\/p>\n
        TCP \u5957\u63a5\u5b57\u63d0\u4f9b\u53ef\u9760\u7684\u3001\u9762\u5411\u8fde\u63a5\u7684\u901a\u4fe1\uff0c\u786e\u4fdd\u6570\u636e\u6309\u987a\u5e8f\u3001\u5b8c\u6574\u5730\u4ece\u4e00\u7aef\u4f20\u8f93\u5230\u53e6\u4e00\u7aef\u3002TCP \u5957\u63a5\u5b57\u5e38\u7528\u4e8e\u9700\u8981\u9ad8\u53ef\u9760\u6027\u548c\u6570\u636e\u5b8c\u6574\u6027\u7684\u5e94\u7528\u7a0b\u5e8f\uff0c\u5982 Web \u670d\u52a1\u5668\u548c\u7535\u5b50\u90ae\u4ef6\u670d\u52a1\u5668\u3002<\/p>\n
        \u4e0e TCP \u4e0d\u540c\uff0cUDP \u5957\u63a5\u5b57\u63d0\u4f9b\u4e0d\u53ef\u9760\u7684\u3001\u65e0\u8fde\u63a5\u7684\u901a\u4fe1\u3002\u5b83\u4eec\u53d1\u9001\u6570\u636e\u5305\u800c\u4e0d\u9700\u8981\u5efa\u7acb\u8fde\u63a5\uff0c\u56e0\u6b64\u4f20\u8f93\u901f\u5ea6\u66f4\u5feb\u3002\u4f46\u662f\uff0c\u5b83\u4eec\u4e0d\u80fd\u4fdd\u8bc1\u6570\u636e\u5305\u7684\u987a\u5e8f\u6216\u5b8c\u6574\u6027\u3002UDP \u5957\u63a5\u5b57\u9002\u7528\u4e8e\u5bf9\u5ef6\u8fdf\u654f\u611f\u4e14\u53ef\u4ee5\u5bb9\u5fcd\u6570\u636e\u4e22\u5931\u7684\u5e94\u7528\u7a0b\u5e8f\uff0c\u5982\u97f3\u9891\u3001\u89c6\u9891\u548c\u5728\u7ebf\u6e38\u620f\u3002<\/p>\n
        \u5728\u7f16\u7a0b\u4e2d\uff0c\u5957\u63a5\u5b57 API\uff08\u5e94\u7528\u7a0b\u5e8f\u7f16\u7a0b\u63a5\u53e3\uff09\u63d0\u4f9b\u4e86\u4e00\u7ec4\u7528\u4e8e\u521b\u5efa\u3001\u7ba1\u7406\u548c\u4e0e\u5957\u63a5\u5b57\u901a\u4fe1\u7684\u51fd\u6570\u3002\u7a0b\u5e8f\u5458\u53ef\u4ee5\u4f7f\u7528\u8fd9\u4e9b\u51fd\u6570\u7f16\u5199\u80fd\u591f\u901a\u8fc7\u7f51\u7edc\u8fdb\u884c\u901a\u4fe1\u7684\u5e94\u7528\u7a0b\u5e8f\u3002\u5e38\u89c1\u7684\u5957\u63a5\u5b57 API \u5305\u62ec Berkeley \u5957\u63a5\u5b57\uff08\u7528\u4e8e Unix \u548c\u7c7b Unix \u7cfb\u7edf\uff09\u548c Winsock\uff08\u7528\u4e8e Windows \u7cfb\u7edf\uff09\u3002<\/p>\n
        \u2478 net.ipv4.tcp_tw_recycle<\/h3>\n
        net.ipv4.tcp_tw_recycle<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u63a7\u5236\u662f\u5426\u542f\u7528\u5feb\u901f\u56de\u6536 TIME_WAIT \u5957\u63a5\u5b57\u7684\u673a\u5236\u3002\u4e0e net.ipv4.tcp_tw_reuse<\/code> \u7c7b\u4f3c\uff0c\u8fd9\u4e2a\u8bbe\u7f6e\u5728\u5927\u91cf\u77ed\u8fde\u63a5\u573a\u666f\u4e0b\u5c24\u4e3a\u91cd\u8981\uff0c\u56e0\u4e3a\u5b83\u53ef\u4ee5\u5e2e\u52a9\u7cfb\u7edf\u66f4\u5feb\u5730\u56de\u6536\u548c\u91cd\u7528 TCP \u7aef\u53e3\u548c\u8d44\u6e90\u3002\u8be5\u53c2\u6570\u5bf9\u5e94\u7cfb\u7edf\u8def\u5f84\u4e3a\uff1a\/proc\/sys\/net\/ipv4\/tcp_tw_recycle\uff0c\u9ed8\u8ba4\u4e3a0<\/p>\n
        net.ipv4.tcp_tw_recycle<\/code> \u53c2\u6570\u7684\u503c\uff1a<\/p>\n
          \n
        • 0<\/code>\uff08\u9ed8\u8ba4\u503c\uff09\uff1a\u7981\u7528 TIME_WAIT \u5957\u63a5\u5b57\u7684\u5feb\u901f\u56de\u6536\u3002<\/li>\n
        • 1<\/code>\uff1a\u542f\u7528 TIME_WAIT \u5957\u63a5\u5b57\u7684\u5feb\u901f\u56de\u6536\u3002\u7cfb\u7edf\u4f1a\u5c3d\u5feb\u56de\u6536\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\uff0c\u51cf\u8f7b\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\u7684\u95ee\u9898\u3002<\/li>\n<\/ul>\n
          \u4e0e net.ipv4.tcp_tw_reuse<\/code> \u4e0d\u540c\uff0cnet.ipv4.tcp_tw_recycle<\/code> \u53c2\u6570\u91c7\u7528\u66f4\u6fc0\u8fdb\u7684\u65b9\u6cd5\u6765\u56de\u6536 TIME_WAIT \u5957\u63a5\u5b57\u3002\u542f\u7528\u6b64\u9009\u9879\u65f6\uff0c\u7cfb\u7edf\u4f1a\u5728\u53ef\u884c\u7684\u60c5\u51b5\u4e0b\u5c3d\u5feb\u56de\u6536 TIME_WAIT \u5957\u63a5\u5b57\uff0c\u800c\u4e0d\u662f\u7b49\u5f85\u5b83\u4eec\u81ea\u7136\u8fc7\u671f\u3002\u8fd9\u6709\u52a9\u4e8e\u51cf\u8f7b\u56e0\u5927\u91cf\u77ed\u8fde\u63a5\u5bfc\u81f4\u7684\u7aef\u53e3\u8d44\u6e90\u8017\u5c3d\u95ee\u9898\u3002<\/p>\n
          \u7136\u800c\uff0c\u542f\u7528 net.ipv4.tcp_tw_recycle<\/code> \u53ef\u80fd\u4f1a\u5bfc\u81f4\u4e0e\u7f51\u7edc\u5730\u5740\u8f6c\u6362\uff08NAT\uff09\u8bbe\u5907\u4e0d\u517c\u5bb9\u7684\u95ee\u9898\u3002\u5728 NAT \u8bbe\u5907\u80cc\u540e\u7684\u5ba2\u6237\u7aef\u53ef\u80fd\u65e0\u6cd5\u4e0e\u542f\u7528\u4e86\u6b64\u9009\u9879\u7684\u670d\u52a1\u5668\u5efa\u7acb\u8fde\u63a5\u3002\u56e0\u6b64\uff0c\u5bf9\u4e8e\u9762\u5411\u516c\u5171\u4e92\u8054\u7f51\u7684\u670d\u52a1\u5668\uff0c\u901a\u5e38\u4e0d\u5efa\u8bae\u542f\u7528 net.ipv4.tcp_tw_recycle<\/code>\u3002<\/p>\n
          \u8981\u67e5\u770b net.ipv4.tcp_tw_recycle<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
          sysctl net.ipv4.tcp_tw_recycle\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u542f\u7528\u5feb\u901f\u56de\u6536 TIME_WAIT \u5957\u63a5\u5b57\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_tw_recycle=1\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_tw_recycle = 1\nsudo sysctl -p<\/code><\/pre>\n
          \u2479 net.ipv4.tcp_syncookies<\/h3>\n
          net.ipv4.tcp_syncookies<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u63a7\u5236\u662f\u5426\u542f\u7528 SYN cookie \u673a\u5236\u3002SYN cookie \u662f\u4e00\u79cd\u9632\u5fa1\u6027\u6280\u672f\uff0c\u7528\u4e8e\u62b5\u6297 SYN \u6d2a\u6c34\u653b\u51fb\uff0c\u8fd9\u662f\u4e00\u79cd\u5206\u5e03\u5f0f\u62d2\u7edd\u670d\u52a1\uff08DDoS\uff09\u653b\u51fb\u7c7b\u578b\u3002SYN \u6d2a\u6c34\u653b\u51fb\u662f\u4e00\u79cd\u62d2\u7edd\u670d\u52a1\uff08DoS\uff09\u653b\u51fb\uff0c\u653b\u51fb\u8005\u901a\u8fc7\u53d1\u9001\u5927\u91cf SYN\uff08\u540c\u6b65\uff09\u6570\u636e\u5305\u6765\u6d88\u8017\u670d\u52a1\u5668\u8d44\u6e90\uff0c\u4ece\u800c\u4f7f\u6b63\u5e38\u7528\u6237\u65e0\u6cd5\u8bbf\u95ee\u670d\u52a1\u5668\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/ipv4\/tcp_syncookies\uff0c\u9ed8\u8ba4\u4e3a1<\/p>\n
          \u5728\u6b63\u5e38\u7684 TCP \u63e1\u624b\u8fc7\u7a0b\u4e2d\uff0c\u5ba2\u6237\u7aef\u53d1\u9001\u4e00\u4e2a SYN \u6570\u636e\u5305\u7ed9\u670d\u52a1\u5668\uff0c\u670d\u52a1\u5668\u54cd\u5e94\u4e00\u4e2a SYN-ACK \u6570\u636e\u5305\uff0c\u7136\u540e\u5ba2\u6237\u7aef\u56de\u590d\u4e00\u4e2a ACK \u6570\u636e\u5305\u3002\u5f53\u670d\u52a1\u5668\u6536\u5230\u5927\u91cf SYN \u6570\u636e\u5305\u65f6\uff0c\u5b83\u9700\u8981\u5206\u914d\u5185\u5b58\u8d44\u6e90\u6765\u8ffd\u8e2a\u6bcf\u4e2a\u6b63\u5728\u5efa\u7acb\u7684\u8fde\u63a5\u3002\u653b\u51fb\u8005\u53ef\u80fd\u53d1\u9001\u5927\u91cf\u4f2a\u9020\u7684 SYN \u6570\u636e\u5305\uff0c\u8feb\u4f7f\u670d\u52a1\u5668\u5206\u914d\u5927\u91cf\u8d44\u6e90\u6765\u5904\u7406\u8fd9\u4e9b\u4e0d\u5b58\u5728\u7684\u8fde\u63a5\uff0c\u4ece\u800c\u5bfc\u81f4\u8d44\u6e90\u8017\u5c3d\u3002<\/p>\n
          \u5f53\u542f\u7528 SYN cookies \u65f6\uff0c\u670d\u52a1\u5668\u4f1a\u4f7f\u7528\u4e00\u79cd\u7279\u6b8a\u7684\u7b97\u6cd5\u6765\u751f\u6210 SYN-ACK \u6570\u636e\u5305\uff0c\u800c\u4e0d\u662f\u5728\u5185\u5b58\u4e2d\u5206\u914d\u8d44\u6e90\u3002\u8fd9\u79cd\u7b97\u6cd5\u4f1a\u5728\u7a0d\u540e\u6536\u5230 ACK \u6570\u636e\u5305\u65f6\u8fdb\u884c\u9a8c\u8bc1\u3002\u8fd9\u6837\uff0c\u670d\u52a1\u5668\u4e0d\u9700\u8981\u4e3a\u6bcf\u4e2a SYN \u6570\u636e\u5305\u5206\u914d\u5185\u5b58\u8d44\u6e90\uff0c\u4ece\u800c\u964d\u4f4e\u4e86\u8d44\u6e90\u6d88\u8017\u3002<\/p>\n
          net.ipv4.tcp_syncookies<\/code> \u53c2\u6570\u7684\u503c\uff1a<\/p>\n
            \n
          • 0<\/code>\uff1a\u7981\u7528 SYN cookies \u673a\u5236\u3002<\/li>\n
          • 1<\/code>\uff08\u9ed8\u8ba4\u503c\uff09\uff1a\u542f\u7528 SYN cookies \u673a\u5236\u3002\u5f53\u670d\u52a1\u5668\u9047\u5230\u5927\u91cf SYN \u8bf7\u6c42\u65f6\uff0c\u4f1a\u542f\u52a8 SYN cookies \u4fdd\u62a4\u3002<\/li>\n<\/ul>\n
            \u8981\u67e5\u770b net.ipv4.tcp_syncookies<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_syncookies\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u7981\u7528 SYN cookies \u673a\u5236\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_syncookies=0\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_syncookies = 0\nsudo sysctl -p<\/code><\/pre>\n
            \u9700\u8981\u6ce8\u610f\u7684\u662f\uff0cSYN cookies \u673a\u5236\u53ef\u80fd\u4f1a\u5bfc\u81f4\u67d0\u4e9b TCP \u6269\u5c55\uff08\u5982\u7a97\u53e3\u7f29\u653e\u548c\u65f6\u95f4\u6233\uff09\u65e0\u6cd5\u4f7f\u7528\u3002\u7136\u800c\uff0c\u5728\u9762\u4e34 SYN \u6d2a\u6c34\u653b\u51fb\u65f6\uff0c\u542f\u7528 SYN cookies \u662f\u4e00\u79cd\u6709\u6548\u7684\u9632\u5fa1\u624b\u6bb5\u3002\u56e0\u6b64\uff0c\u5728\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u4fdd\u6301\u6b64\u9009\u9879\u542f\u7528\u662f\u5408\u7406\u7684\u3002<\/p>\n
            \u247a net.ipv4.ip_local_port_range<\/h3>\n
            net.ipv4.ip_local_port_range<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u5b9a\u4e49\u7cfb\u7edf\u53ef\u7528\u4e8e\u5206\u914d\u7ed9 TCP \u548c UDP \u5957\u63a5\u5b57\u7684\u672c\u5730\u7aef\u53e3\u53f7\u8303\u56f4\u3002\u5f53\u4e00\u4e2a\u5e94\u7528\u7a0b\u5e8f\u53d1\u8d77\u7f51\u7edc\u8fde\u63a5\u6216\u76d1\u542c\u7aef\u53e3\u65f6\uff0c\u7cfb\u7edf\u4f1a\u4ece\u8fd9\u4e2a\u8303\u56f4\u5185\u5206\u914d\u4e00\u4e2a\u53ef\u7528\u7684\u7aef\u53e3\u53f7\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/ipv4\/ip_local_port_range<\/p>\n
            \u6b64\u53c2\u6570\u5305\u542b\u4e24\u4e2a\u6574\u6570\u503c\uff0c\u5206\u522b\u8868\u793a\u7aef\u53e3\u8303\u56f4\u7684\u8d77\u59cb\u548c\u7ed3\u675f\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u8fd9\u4e2a\u8303\u56f4\u901a\u5e38\u8bbe\u7f6e\u4e3a 32768 \u5230 60999\uff0c\u4f46\u6839\u636e\u7cfb\u7edf\u9700\u6c42\u548c\u7f51\u7edc\u73af\u5883\u7684\u4e0d\u540c\uff0c\u60a8\u53ef\u4ee5\u6839\u636e\u9700\u8981\u8c03\u6574\u8fd9\u4e2a\u8303\u56f4\u3002<\/p>\n
            \u8f83\u4f4e\u7684\u7aef\u53e3\u53f7\uff081-1023\uff09\u901a\u5e38\u4fdd\u7559\u7ed9\u7279\u6743\u8fdb\u7a0b\uff08\u5373\uff0c\u9700\u8981 root \u6743\u9650\u7684\u8fdb\u7a0b\uff09\u548c\u4f17\u6240\u5468\u77e5\u7684\u670d\u52a1\uff08\u5982 HTTP\u3001FTP\u3001SSH \u7b49\uff09\u3002\u56e0\u6b64\uff0cnet.ipv4.ip_local_port_range<\/code> \u7684\u8d77\u59cb\u503c\u901a\u5e38\u8bbe\u7f6e\u5728 1024 \u4ee5\u4e0a\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.ip_local_port_range<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.ip_local_port_range\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u7aef\u53e3\u8303\u56f4\u66f4\u6539\u4e3a 20000 \u5230 65000\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.ip_local_port_range="20000 65000"\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.ip_local_port_range = 20000 65000\nsudo sysctl -p<\/code><\/pre>\n
            \u247bnet.ipv4.tcp_max_tw_buckets<\/h3>\n
            net.ipv4.tcp_max_tw_buckets<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u5b9a\u4e49\u7cfb\u7edf\u53ef\u4ee5\u5bb9\u7eb3\u7684\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\u7684\u6700\u5927\u6570\u91cf\u3002TIME_WAIT \u662f TCP \u8fde\u63a5\u5728\u6b63\u5e38\u5173\u95ed\u540e\u8fdb\u5165\u7684\u72b6\u6001\uff0c\u7528\u4e8e\u786e\u4fdd\u5728\u8fde\u63a5\u5173\u95ed\u540e\u4ecd\u80fd\u6b63\u786e\u5904\u7406\u53ef\u80fd\u6b8b\u7559\u7684\u6570\u636e\u5305\u3002\u5728\u8fd9\u4e2a\u72b6\u6001\u4e0b\uff0c\u5957\u63a5\u5b57\u4f1a\u88ab\u4fdd\u7559\u4e00\u6bb5\u65f6\u95f4\uff08\u901a\u5e38\u662f 2 * Maximum Segment Lifetime\uff0c\u7ea6\u4e3a 1-4 \u5206\u949f\uff09\uff0c\u7136\u540e\u88ab\u7cfb\u7edf\u56de\u6536\u3002\u8def\u5f84\uff1a\/proc\/sys\/net\/ipv4\/tcp_max_tw_buckets<\/p>\n
            \u5728\u5904\u7406\u5927\u91cf\u77ed\u8fde\u63a5\u7684\u573a\u666f\u4e0b\uff0c\u53ef\u80fd\u4f1a\u51fa\u73b0\u8bb8\u591a\u5957\u63a5\u5b57\u5904\u4e8e TIME_WAIT \u72b6\u6001\u3002\u8fd9\u53ef\u80fd\u5bfc\u81f4\u7cfb\u7edf\u8d44\u6e90\uff08\u5982\u7aef\u53e3\u548c\u5185\u5b58\uff09\u88ab\u8017\u5c3d\u3002net.ipv4.tcp_max_tw_buckets<\/code> \u53c2\u6570\u7528\u4e8e\u9650\u5236\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\u7684\u6700\u5927\u6570\u91cf\uff0c\u4ee5\u9632\u6b62\u8d44\u6e90\u8017\u5c3d\u3002<\/p>\n
            \u5f53\u5904\u4e8e TIME_WAIT \u72b6\u6001\u7684\u5957\u63a5\u5b57\u6570\u91cf\u8fbe\u5230 net.ipv4.tcp_max_tw_buckets<\/code> \u53c2\u6570\u6307\u5b9a\u7684\u9650\u5236\u65f6\uff0c\u7cfb\u7edf\u5c06\u7acb\u5373\u56de\u6536\u6700\u65e7\u7684 TIME_WAIT \u5957\u63a5\u5b57\u3002\u8fd9\u6709\u52a9\u4e8e\u4fdd\u62a4\u7cfb\u7edf\u514d\u53d7\u56e0\u5927\u91cf TIME_WAIT \u5957\u63a5\u5b57\u5bfc\u81f4\u7684\u8d44\u6e90\u8017\u5c3d\u95ee\u9898\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_max_tw_buckets<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_max_tw_buckets\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u6700\u5927 TIME_WAIT \u5957\u63a5\u5b57\u6570\u91cf\u66f4\u6539\u4e3a 20000\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_max_tw_buckets=20000\n\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_max_tw_buckets = 20000\nsysctl -p<\/code><\/pre>\n
            \u247c net.ipv4.tcp_synack_retries<\/h3>\n
            net.ipv4.tcp_synack_retries<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u63a7\u5236\u670d\u52a1\u5668\u5728 TCP \u63e1\u624b\u8fc7\u7a0b\u4e2d\u53d1\u9001 SYN-ACK\uff08\u540c\u6b65-\u786e\u8ba4\uff09\u6570\u636e\u5305\u7684\u91cd\u8bd5\u6b21\u6570\u3002\u5728 TCP \u63e1\u624b\u8fc7\u7a0b\u4e2d\uff0c\u5ba2\u6237\u7aef\u9996\u5148\u5411\u670d\u52a1\u5668\u53d1\u9001\u4e00\u4e2a SYN\uff08\u540c\u6b65\uff09\u6570\u636e\u5305\uff0c\u670d\u52a1\u5668\u6536\u5230 SYN \u6570\u636e\u5305\u540e\u56de\u590d\u4e00\u4e2a SYN-ACK \u6570\u636e\u5305\uff0c\u5e76\u7b49\u5f85\u5ba2\u6237\u7aef\u53d1\u9001 ACK\uff08\u786e\u8ba4\uff09\u6570\u636e\u5305\u4ee5\u5b8c\u6210\u63e1\u624b\u3002<\/p>\n
            \u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\uff0c\u4f8b\u5982\u7f51\u7edc\u62e5\u585e\u6216\u4e22\u5305\u65f6\uff0c\u670d\u52a1\u5668\u53d1\u9001\u7684 SYN-ACK \u6570\u636e\u5305\u53ef\u80fd\u65e0\u6cd5\u5230\u8fbe\u5ba2\u6237\u7aef\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u670d\u52a1\u5668\u9700\u8981\u91cd\u65b0\u53d1\u9001 SYN-ACK \u6570\u636e\u5305\u3002net.ipv4.tcp_synack_retries<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u670d\u52a1\u5668\u5e94\u91cd\u8bd5\u53d1\u9001 SYN-ACK \u6570\u636e\u5305\u7684\u6b21\u6570<\/p>\n
            net.ipv4.tcp_synack_retries<\/code> \u53c2\u6570\u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 5\u3002\u8fd9\u610f\u5473\u7740\u670d\u52a1\u5668\u5c06\u5c1d\u8bd5\u53d1\u9001 SYN-ACK \u6570\u636e\u5305\u7684\u603b\u6b21\u6570\u4e3a 6\uff08\u5305\u62ec\u9996\u6b21\u53d1\u9001\u548c\u4e4b\u540e\u7684 5 \u6b21\u91cd\u8bd5\uff09\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_synack_retries<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_synack_retries\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u91cd\u8bd5\u6b21\u6570\u66f4\u6539\u4e3a 3\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_synack_retries=3\n\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_synack_retries = 3\nsysctl -p<\/code><\/pre>\n
            \u247d net.ipv4.tcp_syn_retries<\/h3>\n
            net.ipv4.tcp_syn_retries<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e TCP \u8fde\u63a5\u5efa\u7acb\u8fc7\u7a0b\u4e2d SYN \u6570\u636e\u5305\u7684\u91cd\u8bd5\u6b21\u6570\u3002\u5f53\u5ba2\u6237\u7aef\u8bd5\u56fe\u4e0e\u670d\u52a1\u5668\u5efa\u7acb TCP \u8fde\u63a5\u65f6\uff0c\u5b83\u4f1a\u53d1\u9001\u4e00\u4e2a SYN\uff08\u540c\u6b65\uff09\u6570\u636e\u5305\u4ee5\u542f\u52a8 TCP \u63e1\u624b\u8fc7\u7a0b\u3002\u5982\u679c\u670d\u52a1\u5668\u6ca1\u6709\u54cd\u5e94\uff0c\u5ba2\u6237\u7aef\u53ef\u80fd\u9700\u8981\u91cd\u65b0\u53d1\u9001 SYN \u6570\u636e\u5305\u3002net.ipv4.tcp_syn_retries<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u5ba2\u6237\u7aef\u5e94\u8be5\u91cd\u8bd5\u53d1\u9001 SYN \u6570\u636e\u5305\u7684\u6b21\u6570\u3002<\/p>\n
            net.ipv4.tcp_syn_retries<\/code> \u53c2\u6570\u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 6\u3002\u8fd9\u610f\u5473\u7740\u5ba2\u6237\u7aef\u5c06\u5c1d\u8bd5\u53d1\u9001 SYN \u6570\u636e\u5305\u7684\u603b\u6b21\u6570\u4e3a 7\uff08\u5305\u62ec\u9996\u6b21\u53d1\u9001\u548c\u4e4b\u540e\u7684 6 \u6b21\u91cd\u8bd5\uff09\u3002\u5728\u6bcf\u6b21\u91cd\u8bd5\u4e4b\u95f4\uff0c\u5ba2\u6237\u7aef\u4f1a\u7b49\u5f85\u66f4\u957f\u7684\u65f6\u95f4\uff0c\u8fd9\u6837\u5728\u7f51\u7edc\u72b6\u51b5\u4e0d\u4f73\u7684\u60c5\u51b5\u4e0b\uff0c\u4ecd\u7136\u6709\u673a\u4f1a\u5efa\u7acb\u8fde\u63a5\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_syn_retries<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_syn_retries\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06 SYN \u91cd\u8bd5\u6b21\u6570\u66f4\u6539\u4e3a 4\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_syn_retries=4\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_syn_retries = 4\nsysctl -p<\/code><\/pre>\n
            \u247e  net.ipv4.tcp_retries1<\/h3>\n
            net.ipv4.tcp_retries1<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e TCP \u8fde\u63a5\u4e2d\u6570\u636e\u5305\u8f7b\u91cf\u7ea7\u91cd\u8bd5\u7684\u6b21\u6570\u3002\u8fd9\u4e2a\u53c2\u6570\u5b9a\u4e49\u4e86\u5185\u6838\u5728\u8ba4\u4e3a TCP \u8fde\u63a5\u53ef\u80fd\u5b58\u5728\u95ee\u9898\u4e4b\u524d\uff0c\u5c1d\u8bd5\u91cd\u65b0\u53d1\u9001\u672a\u786e\u8ba4\uff08\u672a\u6536\u5230 ACK\uff09\u7684\u6570\u636e\u5305\u7684\u6b21\u6570\u3002\/proc\/sys\/net\/ipv4\/tcp_retries1<\/p>\n
            \u5f53 TCP \u5411\u63a5\u6536\u65b9\u53d1\u9001\u6570\u636e\u5305\u65f6\uff0c\u5b83\u4f1a\u7b49\u5f85\u63a5\u6536\u65b9\u786e\u8ba4\u5df2\u7ecf\u6536\u5230\u6570\u636e\u5305\u3002\u5982\u679c\u5728\u4e00\u5b9a\u65f6\u95f4\u5185\u6ca1\u6709\u6536\u5230\u786e\u8ba4\uff08ACK\uff09\uff0cTCP \u5c06\u5c1d\u8bd5\u91cd\u65b0\u53d1\u9001\u6570\u636e\u5305\u3002net.ipv4.tcp_retries1<\/code> \u53c2\u6570\u6307\u5b9a\u4e86\u5728\u5c06\u8fde\u63a5\u89c6\u4e3a\u6709\u95ee\u9898\u4e4b\u524d\uff0cTCP \u5e94\u8be5\u91cd\u8bd5\u53d1\u9001\u672a\u786e\u8ba4\u6570\u636e\u5305\u7684\u6b21\u6570\u3002<\/p>\n
            net.ipv4.tcp_retries1<\/code> \u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 3\u3002\u8fd9\u610f\u5473\u7740 TCP \u5c06\u5c1d\u8bd5\u91cd\u53d1\u672a\u786e\u8ba4\u7684\u6570\u636e\u5305 3 \u6b21\uff0c\u7136\u540e\u8ba4\u4e3a\u8fde\u63a5\u53ef\u80fd\u6709\u95ee\u9898\u3002\u5982\u679c\u8fde\u63a5\u6709\u95ee\u9898\uff0cTCP \u5c06\u7ee7\u7eed\u91cd\u8bd5\uff0c\u4f46\u4f1a\u6839\u636e net.ipv4.tcp_retries2<\/code> \u53c2\u6570\u6307\u5b9a\u7684\u6b21\u6570\u6765\u786e\u5b9a\u91cd\u8bd5\u6b21\u6570\u3002net.ipv4.tcp_retries2<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u5728\u653e\u5f03\u5c1d\u8bd5\u4e4b\u524d\uff0c\u5c06\u8981\u8fdb\u884c\u7684\u603b\u91cd\u8bd5\u6b21\u6570\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_retries1<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_retries1\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u8f7b\u91cf\u7ea7\u91cd\u8bd5\u6b21\u6570\u66f4\u6539\u4e3a 5\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_retries1=5\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_retries1 = 5\nsudo sysctl -p<\/code><\/pre>\n
            \u247f net.ipv4.tcp_retries2<\/h3>\n
            net.ipv4.tcp_retries2<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e TCP \u8fde\u63a5\u4e2d\u6570\u636e\u5305\u7684\u6700\u5927\u91cd\u8bd5\u6b21\u6570\u3002\u8fd9\u4e2a\u53c2\u6570\u5b9a\u4e49\u4e86\u5728\u653e\u5f03\u5c1d\u8bd5\u91cd\u65b0\u53d1\u9001\u672a\u786e\u8ba4\uff08\u672a\u6536\u5230 ACK\uff09\u7684\u6570\u636e\u5305\u4e4b\u524d\uff0cTCP \u5e94\u8be5\u91cd\u8bd5\u7684\u6b21\u6570\u3002\/proc\/sys\/net\/ipv4\/tcp_retries2<\/p>\n
            \u5728 TCP \u901a\u4fe1\u8fc7\u7a0b\u4e2d\uff0c\u53d1\u9001\u65b9\u4f1a\u7b49\u5f85\u63a5\u6536\u65b9\u786e\u8ba4\u5df2\u6536\u5230\u6570\u636e\u5305\u3002\u5982\u679c\u5728\u4e00\u5b9a\u65f6\u95f4\u5185\u6ca1\u6709\u6536\u5230\u786e\u8ba4\uff08ACK\uff09\uff0c\u53d1\u9001\u65b9\u4f1a\u5c1d\u8bd5\u91cd\u65b0\u53d1\u9001\u6570\u636e\u5305\u3002\u5728\u7ecf\u8fc7\u4e00\u5b9a\u6b21\u6570\u7684\u8f7b\u91cf\u7ea7\u91cd\u8bd5\u4e4b\u540e\uff08\u7531 net.ipv4.tcp_retries1<\/code> \u53c2\u6570\u6307\u5b9a\uff09\uff0c\u8fde\u63a5\u53ef\u80fd\u88ab\u8ba4\u4e3a\u5b58\u5728\u95ee\u9898\u3002net.ipv4.tcp_retries2<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u5728\u653e\u5f03\u5c1d\u8bd5\u4e4b\u524d\uff0c\u5c06\u8981\u8fdb\u884c\u7684\u603b\u91cd\u8bd5\u6b21\u6570\u3002<\/p>\n
            net.ipv4.tcp_retries2<\/code> \u7684\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 15\u3002\u8fd9\u610f\u5473\u7740\uff0c\u5728\u8ba4\u4e3a\u8fde\u63a5\u6709\u95ee\u9898\u4e4b\u540e\uff0cTCP \u5c06\u5c1d\u8bd5\u518d\u8fdb\u884c 15 \u6b21\u91cd\u8bd5\uff0c\u7136\u540e\u653e\u5f03\u5e76\u5173\u95ed\u8fde\u63a5\u3002\u8fd9\u4e9b\u91cd\u8bd5\u6b21\u6570\u5305\u62ec\u4e86 net.ipv4.tcp_retries1<\/code> \u53c2\u6570\u5b9a\u4e49\u7684\u8f7b\u91cf\u7ea7\u91cd\u8bd5\u6b21\u6570<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_retries2<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_retries2\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u6700\u5927\u91cd\u8bd5\u6b21\u6570\u66f4\u6539\u4e3a 10\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_retries2=10\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_retries2 = 10\nsysctl -p<\/code><\/pre>\n
            \u2480 net.ipv4.tcp_keepalive_time<\/h3>\n
            net.ipv4.tcp_keepalive_time<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e TCP \u8fde\u63a5\u7684\u7a7a\u95f2\u4fdd\u6d3b\uff08keepalive\uff09\u65f6\u95f4\u3002TCP keepalive \u662f\u4e00\u4e2a\u53ef\u9009\u7684\u673a\u5236\uff0c\u7528\u4e8e\u68c0\u6d4b TCP \u8fde\u63a5\u662f\u5426\u4ecd\u7136\u6709\u6548\u3002\u5f53\u8fde\u63a5\u5728\u4e00\u6bb5\u65f6\u95f4\u5185\u6ca1\u6709\u4efb\u4f55\u6570\u636e\u4f20\u8f93\u65f6\uff0c\u53d1\u9001\u65b9\u4f1a\u53d1\u9001\u4e00\u4e2a\u7279\u6b8a\u7684\u4fdd\u6d3b\uff08keepalive\uff09\u63a2\u6d4b\u5305\u6765\u786e\u8ba4\u8fde\u63a5\u662f\u5426\u4ecd\u7136\u6709\u6548\u3002\u5982\u679c\u63a5\u6536\u65b9\u6ca1\u6709\u54cd\u5e94\uff0c\u53d1\u9001\u65b9\u53ef\u80fd\u4f1a\u91cd\u8bd5\u53d1\u9001\u4fdd\u6d3b\u63a2\u6d4b\u5305\uff0c\u76f4\u5230\u8fbe\u5230\u6700\u5927\u91cd\u8bd5\u6b21\u6570\u540e\u653e\u5f03\u5e76\u5173\u95ed\u8fde\u63a5\u3002<\/p>\n
            net.ipv4.tcp_keepalive_time<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u5728\u53d1\u9001\u7b2c\u4e00\u4e2a\u4fdd\u6d3b\u63a2\u6d4b\u5305\u4e4b\u524d\uff0c\u8fde\u63a5\u5fc5\u987b\u4fdd\u6301\u7a7a\u95f2\u7684\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\u3002\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 7200 \u79d2\uff082 \u5c0f\u65f6\uff09\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_keepalive_time<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_keepalive_time\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u4fdd\u6d3b\u65f6\u95f4\u66f4\u6539\u4e3a 3600 \u79d2\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_keepalive_time=3600\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_keepalive_time = 3600\nsysctl -p<\/code><\/pre>\n
            \u2481net.ipv4.tcp_keepalive_probes<\/h3>\n
            net.ipv4.tcp_keepalive_probes<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e TCP \u4fdd\u6d3b\uff08keepalive\uff09\u63a2\u6d4b\u5305\u7684\u6700\u5927\u91cd\u8bd5\u6b21\u6570\u3002TCP keepalive \u662f\u4e00\u79cd\u53ef\u9009\u7684\u673a\u5236\uff0c\u7528\u4e8e\u68c0\u6d4b TCP \u8fde\u63a5\u662f\u5426\u4ecd\u7136\u6709\u6548\u3002\u5f53\u8fde\u63a5\u5728\u4e00\u6bb5\u65f6\u95f4\u5185\u6ca1\u6709\u4efb\u4f55\u6570\u636e\u4f20\u8f93\u65f6\uff0c\u53d1\u9001\u65b9\u4f1a\u53d1\u9001\u4e00\u4e2a\u7279\u6b8a\u7684\u4fdd\u6d3b\u63a2\u6d4b\u5305\u6765\u786e\u8ba4\u8fde\u63a5\u662f\u5426\u4ecd\u7136\u6709\u6548\u3002\u5982\u679c\u63a5\u6536\u65b9\u6ca1\u6709\u54cd\u5e94\uff0c\u53d1\u9001\u65b9\u4f1a\u91cd\u8bd5\u53d1\u9001\u4fdd\u6d3b\u63a2\u6d4b\u5305\u3002<\/p>\n
            net.ipv4.tcp_keepalive_probes<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u5728\u653e\u5f03\u5e76\u5173\u95ed\u8fde\u63a5\u4e4b\u524d\uff0c\u53d1\u9001\u65b9\u5e94\u8be5\u91cd\u8bd5\u53d1\u9001\u4fdd\u6d3b\u63a2\u6d4b\u5305\u7684\u6b21\u6570\u3002\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 9 \u6b21\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_keepalive_probes<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_keepalive_probes\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u4fdd\u6d3b\u63a2\u6d4b\u5305\u7684\u6700\u5927\u91cd\u8bd5\u6b21\u6570\u66f4\u6539\u4e3a 5 \u6b21\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_keepalive_probes=5\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_keepalive_probes = 5\nsudo sysctl -p<\/code><\/pre>\n
            \u2482 net.ipv4.tcp_keepalive_intvl<\/h3>\n
            net.ipv4.tcp_keepalive_intvl<\/code> \u662f\u4e00\u4e2a Linux \u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u8bbe\u7f6e TCP \u4fdd\u6d3b\uff08keepalive\uff09\u63a2\u6d4b\u5305\u4e4b\u95f4\u7684\u65f6\u95f4\u95f4\u9694\u3002TCP keepalive \u662f\u4e00\u79cd\u53ef\u9009\u7684\u673a\u5236\uff0c\u7528\u4e8e\u68c0\u6d4b TCP \u8fde\u63a5\u662f\u5426\u4ecd\u7136\u6709\u6548\u3002\u5f53\u8fde\u63a5\u5728\u4e00\u6bb5\u65f6\u95f4\u5185\u6ca1\u6709\u4efb\u4f55\u6570\u636e\u4f20\u8f93\u65f6\uff0c\u53d1\u9001\u65b9\u4f1a\u53d1\u9001\u4e00\u4e2a\u7279\u6b8a\u7684\u4fdd\u6d3b\u63a2\u6d4b\u5305\u6765\u786e\u8ba4\u8fde\u63a5\u662f\u5426\u4ecd\u7136\u6709\u6548\u3002\u5982\u679c\u63a5\u6536\u65b9\u6ca1\u6709\u54cd\u5e94\uff0c\u53d1\u9001\u65b9\u4f1a\u91cd\u8bd5\u53d1\u9001\u4fdd\u6d3b\u63a2\u6d4b\u5305\u3002<\/p>\n
            net.ipv4.tcp_keepalive_intvl<\/code> \u53c2\u6570\u5b9a\u4e49\u4e86\u53d1\u9001\u65b9\u5728\u8fde\u7eed\u53d1\u9001\u4fdd\u6d3b\u63a2\u6d4b\u5305\u4e4b\u95f4\u5e94\u8be5\u7b49\u5f85\u7684\u65f6\u95f4\uff08\u4ee5\u79d2\u4e3a\u5355\u4f4d\uff09\u3002\u9ed8\u8ba4\u503c\u901a\u5e38\u4e3a 75 \u79d2\u3002<\/p>\n
            \u8981\u67e5\u770b net.ipv4.tcp_keepalive_intvl<\/code> \u7684\u5f53\u524d\u503c\uff0c\u53ef\u4ee5\u5728 Linux \u7cfb\u7edf\u4e2d\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a<\/p>\n
            sysctl net.ipv4.tcp_keepalive_intvl\n#\u8981\u8bbe\u7f6e\u65b0\u7684\u503c\uff08\u4f8b\u5982\uff0c\u5c06\u4fdd\u6d3b\u63a2\u6d4b\u5305\u4e4b\u95f4\u7684\u65f6\u95f4\u95f4\u9694\u66f4\u6539\u4e3a 60 \u79d2\uff09\uff0c\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u547d\u4ee4\uff1a\nsudo sysctl -w net.ipv4.tcp_keepalive_intvl=60\n#\u8981\u4f7f\u66f4\u6539\u6c38\u4e45\u751f\u6548\uff0c\u9700\u8981\u5728 \/etc\/sysctl.conf \u6587\u4ef6\u4e2d\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a\nnet.ipv4.tcp_keepalive_intvl = 60\nsudo sysctl -p<\/code><\/pre>\n
            \u2483 net.ipv4.ip_forward=0<\/h3>\n
            net.ipv4.ip_forward<\/code> \u662f\u4e00\u4e2a Linux \u7cfb\u7edf\u5185\u6838\u53c2\u6570\uff0c\u7528\u4e8e\u63a7\u5236 IPv4 \u6570\u636e\u5305\u5728\u4e0d\u540c\u7f51\u7edc\u63a5\u53e3\u4e4b\u95f4\u7684\u8f6c\u53d1\u529f\u80fd\u3002\u8be5\u53c2\u6570\u53ef\u4ee5\u8bbe\u7f6e\u4e3a 0<\/code> \u6216 1<\/code>\u3002<\/p>\n
              \n
            • net.ipv4.ip_forward=0<\/code>\uff1aIP \u8f6c\u53d1\u529f\u80fd\u7981\u7528\u3002\u5f53\u8bbe\u7f6e\u4e3a 0<\/code> \u65f6\uff0c\u7cfb\u7edf\u5c06\u4e0d\u4f1a\u8f6c\u53d1\u6536\u5230\u7684 IPv4 \u6570\u636e\u5305\u3002\u8fd9\u610f\u5473\u7740\uff0c\u5982\u679c\u6570\u636e\u5305\u4e0d\u662f\u76ee\u7684\u5730\u4e3a\u672c\u5730\u7cfb\u7edf\u7684\uff0c\u5b83\u5c06\u88ab\u4e22\u5f03\u3002\u5927\u591a\u6570\u4e2a\u4eba\u8ba1\u7b97\u673a\u548c\u670d\u52a1\u5668\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u5c06\u6b64\u53c2\u6570\u8bbe\u7f6e\u4e3a 0<\/code>\uff0c\u56e0\u4e3a\u5b83\u4eec\u901a\u5e38\u4e0d\u9700\u8981\u5145\u5f53\u8def\u7531\u5668\u6216\u7f51\u5173\u3002<\/li>\n
            • net.ipv4.ip_forward=1<\/code>\uff1aIP \u8f6c\u53d1\u529f\u80fd\u542f\u7528\u3002\u5f53\u8bbe\u7f6e\u4e3a 1<\/code> \u65f6\uff0c\u7cfb\u7edf\u5c06\u5141\u8bb8 IPv4 \u6570\u636e\u5305\u5728\u4e0d\u540c\u7f51\u7edc\u63a5\u53e3\u4e4b\u95f4\u8f6c\u53d1\u3002\u8fd9\u4f7f\u5f97 Linux \u7cfb\u7edf\u53ef\u4ee5\u5145\u5f53\u8def\u7531\u5668\u6216\u7f51\u5173\uff0c\u5c06\u6570\u636e\u5305\u4ece\u4e00\u4e2a\u7f51\u7edc\u63a5\u53e3\u4f20\u9012\u5230\u53e6\u4e00\u4e2a\u7f51\u7edc\u63a5\u53e3\u3002\u6b64\u8bbe\u7f6e\u5728\u67d0\u4e9b\u7279\u5b9a\u573a\u666f\u4e0b\u662f\u5fc5\u9700\u7684\uff0c\u4f8b\u5982\u642d\u5efa VPN \u670d\u52a1\u5668\u3001\u7f51\u7edc\u5730\u5740\u8f6c\u6362 (NAT) \u6216\u6784\u5efa\u8def\u7531\u5668\u7b49\u3002<\/li>\n<\/ul>\n
              \u53ef\u4ee5\u901a\u8fc7\u4ee5\u4e0b\u65b9\u6cd5\u68c0\u67e5\u548c\u4fee\u6539 net.ipv4.ip_forward<\/code> \u7684\u503c\uff1a<\/p>\n
                \n
              1. \u67e5\u770b\u5f53\u524d\u8bbe\u7f6e\uff1a<\/li>\n<\/ol>\n
                cat \/proc\/sys\/net\/ipv4\/ip_forward<\/code><\/pre>\n
                  \n
                1. \u4e34\u65f6\u4fee\u6539\u8bbe\u7f6e\uff08\u91cd\u542f\u540e\u5931\u6548\uff09\uff1a<\/li>\n<\/ol>\n
                  \u542f\u7528ip\u8f6c\u53d1<\/p>\n
                  echo 1 | sudo tee \/proc\/sys\/net\/ipv4\/ip_forward<\/code><\/pre>\n
                  \u7981\u7528 IP \u8f6c\u53d1\uff1a<\/p>\n
                  echo 0 | sudo tee \/proc\/sys\/net\/ipv4\/ip_forward<\/code><\/pre>\n
                    \n
                  1. \u6c38\u4e45\u4fee\u6539\u8bbe\u7f6e\uff08\u901a\u8fc7\u4fee\u6539 \/etc\/sysctl.conf \u6587\u4ef6\uff09\uff1a<\/li>\n<\/ol>\n
                    \u4f7f\u7528\u6587\u672c\u7f16\u8f91\u5668\u6253\u5f00 \/etc\/sysctl.conf<\/code> \u6587\u4ef6\uff0c\u4f8b\u5982\u4f7f\u7528 vi<\/code>\uff1a<\/p>\n
                    sudo vi \/etc\/sysctl.conf<\/code><\/pre>\n
                    \u627e\u5230 net.ipv4.ip_forward<\/code> \u53c2\u6570\uff0c\u8bbe\u7f6e\u4e3a 0<\/code>\uff08\u7981\u7528\uff09\u6216 1<\/code>\uff08\u542f\u7528\uff09\uff0c\u5e76\u4fdd\u5b58\u6587\u4ef6\u3002\u4f8b\u5982\uff0c\u8981\u7981\u7528 IP \u8f6c\u53d1\uff0c\u6dfb\u52a0\u6216\u4fee\u6539\u4ee5\u4e0b\u884c\uff1a<\/p>\n
                    net.ipv4.ip_forward=0<\/code><\/pre>\n
                    \u4f7f\u66f4\u6539\u7acb\u5373\u751f\u6548\uff1a<\/p>\n
                    sudo sysctl -p<\/code><\/pre>\n
                    IP \u8f6c\u53d1\u529f\u80fd<\/h4>\n
                    IP \u8f6c\u53d1\u529f\u80fd\uff08IP forwarding\uff09\u662f\u6307\u7f51\u7edc\u8bbe\u5907\uff08\u5982\u8def\u7531\u5668\u6216\u5177\u6709\u591a\u4e2a\u7f51\u7edc\u63a5\u53e3\u7684\u8ba1\u7b97\u673a\uff09\u5728\u63a5\u6536\u5230 IP \u6570\u636e\u5305\u540e\uff0c\u6839\u636e\u6570\u636e\u5305\u7684\u76ee\u6807\u5730\u5740\u5c06\u5176\u8f6c\u53d1\u5230\u6b63\u786e\u7684\u7f51\u7edc\u63a5\u53e3\u548c\u4e0b\u4e00\u8df3\u8bbe\u5907\uff0c\u4ee5\u4fbf\u6570\u636e\u5305\u6700\u7ec8\u5230\u8fbe\u76ee\u7684\u5730\u3002<\/p>\n
                    \u5728\u7b80\u5355\u7684\u7f51\u7edc\u73af\u5883\u4e2d\uff0c\u8bbe\u5907\u4e4b\u95f4\u53ef\u4ee5\u76f4\u63a5\u901a\u4fe1\uff0c\u65e0\u9700\u8f6c\u53d1\u3002\u4f46\u5728\u66f4\u590d\u6742\u7684\u7f51\u7edc\u62d3\u6251\u4e2d\uff0c\u6570\u636e\u5305\u901a\u5e38\u9700\u8981\u5728\u591a\u4e2a\u8bbe\u5907\u4e4b\u95f4\u8fdb\u884c\u8f6c\u53d1\uff0c\u4ee5\u4fbf\u4ece\u6e90\u8bbe\u5907\u4f20\u8f93\u5230\u76ee\u7684\u8bbe\u5907\u3002IP \u8f6c\u53d1\u529f\u80fd\u662f\u5b9e\u73b0\u8fd9\u4e00\u8fc7\u7a0b\u7684\u5173\u952e\u3002<\/p>\n
                    \u5f53\u4e00\u53f0\u8ba1\u7b97\u673a\u5177\u6709\u591a\u4e2a\u7f51\u7edc\u63a5\u53e3\uff0c\u4f8b\u5982\u8fde\u63a5\u5230\u4e0d\u540c\u7684\u5b50\u7f51\u6216 VLAN \u65f6\uff0cIP \u8f6c\u53d1\u529f\u80fd\u53ef\u4ee5\u8ba9\u8fd9\u53f0\u8ba1\u7b97\u673a\u5145\u5f53\u8def\u7531\u5668\u6216\u7f51\u5173\u7684\u89d2\u8272\uff0c\u5c06\u6570\u636e\u5305\u4ece\u4e00\u4e2a\u7f51\u7edc\u63a5\u53e3\u8f6c\u53d1\u5230\u53e6\u4e00\u4e2a\u7f51\u7edc\u63a5\u53e3\u3002\u8fd9\u5bf9\u4e8e\u5b9e\u73b0\u4e92\u8054\u7f51\u8fde\u63a5\u5171\u4eab\u3001\u6784\u5efa VPN \u7f51\u5173\u6216\u642d\u5efa\u9632\u706b\u5899\u7b49\u573a\u666f\u975e\u5e38\u6709\u7528\u3002<\/p>\n
                    \u5728 Linux \u7cfb\u7edf\u4e2d\uff0cIP \u8f6c\u53d1\u529f\u80fd\u53ef\u4ee5\u901a\u8fc7\u5185\u6838\u53c2\u6570 net.ipv4.ip_forward<\/code> \u8fdb\u884c\u542f\u7528\u6216\u7981\u7528\u3002\u503c\u4e3a 0<\/code> \u8868\u793a\u7981\u7528\uff0c\u503c\u4e3a 1<\/code> \u8868\u793a\u542f\u7528\u3002\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5927\u591a\u6570\u7cfb\u7edf\u4f1a\u7981\u7528 IP \u8f6c\u53d1\u529f\u80fd\uff0c\u56e0\u4e3a\u4e0d\u9700\u8981\u5145\u5f53\u8def\u7531\u5668\u6216\u7f51\u5173\u3002\u4f46\u5728\u9700\u8981\u65f6\uff0c\u53ef\u4ee5\u6839\u636e\u5b9e\u9645\u9700\u6c42\u542f\u7528 IP \u8f6c\u53d1\u529f\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
                    TCP\u5185\u6838\u53c2\u6570 1.\u4fee\u6539TCP\u5185\u6838\u53c2\u6570 systcl.conf \u5728Linux\u7cfb\u7edf\u4e2d\uff0c\/proc\/sy […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[38],"tags":[39,40],"views":250,"_links":{"self":[{"href":"http:\/\/8.141.4.74\/index.php?rest_route=\/wp\/v2\/posts\/351"}],"collection":[{"href":"http:\/\/8.141.4.74\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/8.141.4.74\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/8.141.4.74\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/8.141.4.74\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=351"}],"version-history":[{"count":1,"href":"http:\/\/8.141.4.74\/index.php?rest_route=\/wp\/v2\/posts\/351\/revisions"}],"predecessor-version":[{"id":352,"href":"http:\/\/8.141.4.74\/index.php?rest_route=\/wp\/v2\/posts\/351\/revisions\/352"}],"wp:attachment":[{"href":"http:\/\/8.141.4.74\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=351"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/8.141.4.74\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=351"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/8.141.4.74\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=351"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}