{"id":1643,"date":"2016-05-05T14:31:51","date_gmt":"2016-05-05T06:31:51","guid":{"rendered":"\/wp\/?p=1643"},"modified":"2016-05-05T14:31:51","modified_gmt":"2016-05-05T06:31:51","slug":"%e3%80%90%e8%bd%ac%e3%80%91tcp-%e7%8a%b6%e6%80%81%e8%bd%ac%e6%8d%a2","status":"publish","type":"post","link":"https:\/\/tixbay.net\/?p=1643","title":{"rendered":"\u3010\u8f6c\u3011TCP \u72b6\u6001\u8f6c\u6362"},"content":{"rendered":"

\"544465b00200001s\"<\/a><\/p>\n

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\nSYN_RCVD: \u8fd9\u4e2a\u72b6\u6001\u8868\u793a\u63a5\u53d7\u5230\u4e86SYN\u62a5\u6587\uff0c\u5728\u6b63\u5e38\u60c5\u51b5\u4e0b\uff0c\u8fd9\u4e2a\u72b6\u6001\u662f\u670d\u52a1\u5668\u7aef\u7684SOCKET\u5728\u5efa\u7acbTCP\u8fde\u63a5\u65f6\u7684\u4e09\u6b21\u63e1\u624b\u4f1a\u8bdd\u8fc7\u7a0b\u4e2d\u7684\u4e00\u4e2a\u4e2d\u95f4\u72b6\u6001\uff0c\u5f88\u77ed\u6682\uff0c\u57fa\u672c \u4e0a\u7528netstat\u4f60\u662f\u5f88\u96be\u770b\u5230\u8fd9\u79cd\u72b6\u6001\u7684\uff0c\u9664\u975e\u4f60\u7279\u610f\u5199\u4e86\u4e00\u4e2a\u5ba2\u6237\u7aef\u6d4b\u8bd5\u7a0b\u5e8f\uff0c\u6545\u610f\u5c06\u4e09\u6b21TCP\u63e1\u624b\u8fc7\u7a0b\u4e2d\u6700\u540e\u4e00\u4e2aACK\u62a5\u6587\u4e0d\u4e88\u53d1\u9001\u3002\u56e0\u6b64\u8fd9\u79cd\u72b6\u6001 \u65f6\uff0c\u5f53\u6536\u5230\u5ba2\u6237\u7aef\u7684ACK\u62a5\u6587\u540e\uff0c\u5b83\u4f1a\u8fdb\u5165\u5230ESTABLISHED\u72b6\u6001\u3002
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\nFIN_WAIT_2\uff1a\u4e0a\u9762\u5df2\u7ecf\u8be6\u7ec6\u89e3\u91ca\u4e86\u8fd9\u79cd\u72b6\u6001\uff0c\u5b9e\u9645\u4e0aFIN_WAIT_2\u72b6\u6001\u4e0b\u7684SOCKET\uff0c\u8868\u793a\u534a\u8fde\u63a5\uff0c\u4e5f\u5373\u6709\u4e00\u65b9\u8981\u6c42close\u8fde\u63a5\uff0c\u4f46\u53e6\u5916\u8fd8\u544a\u8bc9\u5bf9\u65b9\uff0c\u6211\u6682\u65f6\u8fd8\u6709\u70b9\u6570\u636e\u9700\u8981\u4f20\u9001\u7ed9\u4f60\uff0c\u7a0d\u540e\u518d\u5173\u95ed\u8fde\u63a5\u3002
\nTIME_WAIT: \u8868\u793a\u6536\u5230\u4e86\u5bf9\u65b9\u7684FIN\u62a5\u6587\uff0c\u5e76\u53d1\u9001\u51fa\u4e86ACK\u62a5\u6587\uff0c\u5c31\u7b492MSL\u540e\u5373\u53ef\u56de\u5230CLOSED\u53ef\u7528\u72b6\u6001\u4e86\u3002\u5982\u679cFIN_WAIT_1\u72b6\u6001\u4e0b\uff0c\u6536\u5230\u4e86\u5bf9\u65b9\u540c\u65f6\u5e26 FIN\u6807\u5fd7\u548cACK\u6807\u5fd7\u7684\u62a5\u6587\u65f6\uff0c\u53ef\u4ee5\u76f4\u63a5\u8fdb\u5165\u5230TIME_WAIT\u72b6\u6001\uff0c\u800c\u65e0\u987b\u7ecf\u8fc7FIN_WAIT_2\u72b6\u6001\u3002
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\nCLOSE_WAIT: \u8fd9\u79cd\u72b6\u6001\u7684\u542b\u4e49\u5176\u5b9e\u662f\u8868\u793a\u5728\u7b49\u5f85\u5173\u95ed\u3002\u600e\u4e48\u7406\u89e3\u5462\uff1f\u5f53\u5bf9\u65b9close\u4e00\u4e2aSOCKET\u540e\u53d1\u9001FIN\u62a5\u6587\u7ed9\u81ea\u5df1\uff0c\u4f60\u7cfb\u7edf\u6beb\u65e0\u7591\u95ee\u5730\u4f1a\u56de\u5e94\u4e00\u4e2aACK\u62a5\u6587\u7ed9\u5bf9 \u65b9\uff0c\u6b64\u65f6\u5219\u8fdb\u5165\u5230CLOSE_WAIT\u72b6\u6001\u3002\u63a5\u4e0b\u6765\u5462\uff0c\u5b9e\u9645\u4e0a\u4f60\u771f\u6b63\u9700\u8981\u8003\u8651\u7684\u4e8b\u60c5\u662f\u5bdf\u770b\u4f60\u662f\u5426\u8fd8\u6709\u6570\u636e\u53d1\u9001\u7ed9\u5bf9\u65b9\uff0c\u5982\u679c\u6ca1\u6709\u7684\u8bdd\uff0c\u90a3\u4e48\u4f60\u4e5f\u5c31\u53ef\u4ee5 close\u8fd9\u4e2aSOCKET\uff0c\u53d1\u9001FIN\u62a5\u6587\u7ed9\u5bf9\u65b9\uff0c\u4e5f\u5373\u5173\u95ed\u8fde\u63a5\u3002\u6240\u4ee5\u4f60\u5728CLOSE_WAIT\u72b6\u6001\u4e0b\uff0c\u9700\u8981\u5b8c\u6210\u7684\u4e8b\u60c5\u662f\u7b49\u5f85\u4f60\u53bb\u5173\u95ed\u8fde\u63a5\u3002
\nLAST_ACK: \u8fd9\u4e2a\u72b6\u6001\u8fd8\u662f\u6bd4\u8f83\u5bb9\u6613\u597d\u7406\u89e3\u7684\uff0c\u5b83\u662f\u88ab\u52a8\u5173\u95ed\u4e00\u65b9\u5728\u53d1\u9001FIN\u62a5\u6587\u540e\uff0c\u6700\u540e\u7b49\u5f85\u5bf9\u65b9\u7684ACK\u62a5\u6587\u3002\u5f53\u6536\u5230ACK\u62a5\u6587\u540e\uff0c\u4e5f\u5373\u53ef\u4ee5\u8fdb\u5165\u5230CLOSED\u53ef\u7528\u72b6\u6001\u4e86\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"

1\u3001\u5efa\u7acb\u8fde\u63a5\u534f\u8bae\uff08\u4e09\u6b21\u63e1\u624b\uff09 \uff081\uff09\u5ba2\u6237\u7aef\u53d1\u9001\u4e00\u4e2a\u5e26SYN\u6807\u5fd7\u7684TCP\u62a5\u6587\u5230\u670d\u52a1 …<\/p>\n

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