{"id":237,"date":"2021-11-21T13:57:08","date_gmt":"2021-11-21T13:57:08","guid":{"rendered":"http:\/\/47.103.123.166\/?p=237"},"modified":"2021-11-21T14:03:42","modified_gmt":"2021-11-21T14:03:42","slug":"%e5%a5%87%e6%80%aa%e7%9a%84%e7%9f%a5%e8%af%86%e5%8f%88%e5%a2%9e%e5%8a%a0%e4%ba%865-tcp","status":"publish","type":"post","link":"http:\/\/47.103.123.166\/?p=237","title":{"rendered":"\u5947\u602a\u7684\u77e5\u8bc6\u53c8\u589e\u52a0\u4e865\u2014\u2014TCP"},"content":{"rendered":"
    \n
  1. \u8fd9\u7bc7 TCP \u3001UDP \u7edd\u4e86\uff01<\/a><\/li>\n
  2. \u4f60\u8fd8\u5728\u4e3a TCP \u91cd\u4f20\u3001\u6ed1\u52a8\u7a97\u53e3\u3001\u6d41\u91cf\u63a7\u5236\u3001\u62e5\u585e\u63a7\u5236\u53d1\u6101\u5417\uff1f\u770b\u5b8c\u56fe\u89e3\u5c31\u4e0d\u6101\u4e86…<\/a><\/li>\n
  3. \n

    TIME_WAIT<\/a>
    \n TIME_WAIT\u662f\u4e3b\u52a8\u5173\u95ed\u7684\u4e00\u65b9\u4ea7\u751f\u7684\uff0c\u4e00\u822c\u662fclient\u3002
    \n TCP\u8fde\u63a5\u4e2d\uff0c\u4e3b\u52a8\u5173\u95ed\u7684\u4e00\u65b9\u5728\u5173\u95ed\u540e\u7684\u4e00\u6bb5\u65f6\u95f4\u5185\u4fdd\u6301\u4e00\u4e2aTIME_WAIT\u7684\u72b6\u6001\u3002
    \n \u72b6\u6001\u7ef4\u6301\u65f6\u95f4\u4e00\u822c\u662f2MSL\uff08Maximum Segment Lifetime\uff0c\u6700\u5927\u5206\u6bb5\u5bff\u547d\uff09\uff0c\u4f5c\u7528\u6709\u4e24\u70b9\uff1a
    \n   \uff081\uff09\u4fdd\u8bc1\u8fde\u63a5\u6b63\u5e38\u7ec8\u6b62
    \n   \uff082\uff09\u4fdd\u8bc1\u7f51\u7edc\u4e2d\u672a\u63a5\u6536\u7684\u6570\u636e\u5305\u6b63\u5e38\u8fc7\u671f<\/p>\n

    \n

    \u6458\u62841
    \n\u6682\u4ee5 A\u3001B \u6765\u4ee3\u6307 TCP \u8fde\u63a5\u7684\u4e24\u7aef\uff0cA \u4e3a\u4e3b\u52a8\u5173\u95ed\u7684\u4e00\u7aef\u3002
    \n1\u3001\u56db\u6b21\u6325\u624b\u4e2d\uff0cA \u53d1 FIN\uff0c B \u54cd\u5e94 ACK\uff0cB \u518d\u53d1 FIN\uff0cA \u54cd\u5e94 ACK \u5b9e\u73b0\u8fde\u63a5\u7684\u5173\u95ed\u3002\u800c\u5982\u679c A \u54cd\u5e94\u7684 ACK \u5305\u4e22\u5931\uff0cB \u4f1a\u4ee5\u4e3a A \u6ca1\u6709\u6536\u5230\u81ea\u5df1\u7684\u5173\u95ed\u8bf7\u6c42\uff0c\u7136\u540e\u4f1a\u91cd\u8bd5\u5411 A \u518d\u53d1 FIN \u5305\u3002
    \n\u5982\u679c\u6ca1\u6709 TIME_WAIT \u72b6\u6001\uff0cA \u4e0d\u518d\u4fdd\u5b58\u8fd9\u4e2a\u8fde\u63a5\u7684\u4fe1\u606f\uff0c\u6536\u5230\u4e00\u4e2a\u4e0d\u5b58\u5728\u7684\u8fde\u63a5\u7684\u5305\uff0cA \u4f1a\u54cd\u5e94 RST \u5305\uff0c\u5bfc\u81f4 B \u7aef\u5f02\u5e38\u54cd\u5e94\u3002
    \n\u6b64\u65f6\uff0c TIME_WAIT \u662f\u4e3a\u4e86\u4fdd\u8bc1\u5168\u53cc\u5de5\u7684 TCP \u8fde\u63a5\u6b63\u5e38\u7ec8\u6b62\u3002
    \n2\u3001TCP \u4e0b\u7684 IP \u5c42\u534f\u8bae\u662f\u65e0\u6cd5\u4fdd\u8bc1\u5305\u4f20\u8f93\u7684\u5148\u540e\u987a\u5e8f\u7684\u3002\u5982\u679c\u53cc\u65b9\u6325\u624b\u4e4b\u540e\uff0c\u4e00\u4e2a\u7f51\u7edc\u56db\u5143\u7ec4\uff08src\/dst ip\/port\uff09\u88ab\u56de\u6536\uff0c\u800c\u6b64\u65f6\u7f51\u7edc\u4e2d\u8fd8\u6709\u4e00\u4e2a\u8fdf\u5230\u7684\u6570\u636e\u5305\u6ca1\u6709\u88ab B \u63a5\u6536\uff0cA \u5e94\u7528\u7a0b\u5e8f\u53c8\u7acb\u523b\u4f7f\u7528\u4e86\u540c\u6837\u7684\u56db\u5143\u7ec4\u518d\u521b\u5efa\u4e86\u4e00\u4e2a\u65b0\u7684\u8fde\u63a5\u540e\uff0c\u8fd9\u4e2a\u8fdf\u5230\u7684\u6570\u636e\u5305\u624d\u5230\u8fbe B\uff0c\u90a3\u4e48\u8fd9\u4e2a\u6570\u636e\u5305\u5c31\u4f1a\u8ba9 B \u4ee5\u4e3a\u662f A \u521a\u53d1\u8fc7\u6765\u7684\u3002
    \n\u6b64\u65f6\uff0c TIME_WAIT \u7684\u5b58\u5728\u662f\u4e3a\u4e86\u4fdd\u8bc1\u7f51\u7edc\u4e2d\u8ff7\u5931\u7684\u6570\u636e\u5305\u6b63\u5e38\u8fc7\u671f\u3002
    \n\u6458\u62842\uff1a\u65f6\u957f\u7684\u786e\u5b9a
    \n\u7531\u539f\u56e0\u6765\u63a8\u5b9e\u73b0\uff0cTIME_WAIT \u72b6\u6001\u7684\u4fdd\u6301\u65f6\u957f\u4e5f\u5c31\u53ef\u4ee5\u7406\u89e3\u4e86\u3002\u786e\u5b9a TIME_WAIT \u7684\u65f6\u957f\u4e3b\u8981\u8003\u8651\u4e0a\u6587\u7684\u7b2c\u4e8c\u79cd\u60c5\u51b5\uff0c\u4fdd\u8bc1\u5173\u95ed\u8fde\u63a5\u540e\u8fd9\u4e2a\u8fde\u63a5\u5728\u7f51\u7edc\u4e2d\u7684\u6240\u6709\u6570\u636e\u5305\u90fd\u8fc7\u671f\u3002
    \n\u8bf4\u5230\u8fc7\u671f\u65f6\u95f4\uff0c\u4e0d\u5f97\u4e0d\u63d0\u53e6\u4e00\u4e2a\u6982\u5ff5: \u6700\u5927\u5206\u6bb5\u5bff\u547d\uff08MSL, Maximum Segment Lifetime\uff09\uff0c\u5b83\u8868\u793a\u4e00\u4e2a TCP \u5206\u6bb5\u53ef\u4ee5\u5b58\u5728\u4e8e\u4e92\u8054\u7f51\u7cfb\u7edf\u4e2d\u7684\u6700\u5927\u65f6\u95f4\uff0c\u7531 TCP \u7684\u5b9e\u73b0\uff0c\u8d85\u51fa\u8fd9\u4e2a\u5bff\u547d\u7684\u5206\u7247\u90fd\u4f1a\u88ab\u4e22\u5f03\u3002
    \nTIME_WAIT \u72b6\u6001\u7531\u4e3b\u52a8\u5173\u95ed\u7684 A \u6765\u4fdd\u6301\uff0c\u90a3\u4e48\u6211\u4eec\u6765\u8003\u8651\u5bf9\u4e8e A \u6765\u8bf4\uff0c\u53ef\u80fd\u63a5\u5230\u4e0a\u4e00\u4e2a\u8fde\u63a5\u7684\u6570\u636e\u5305\u7684\u6700\u5927\u65f6\u957f\uff1aA \u521a\u53d1\u51fa\u7684\u6570\u636e\u5305\uff0c\u80fd\u4fdd\u6301 MSL \u65f6\u957f\u7684\u5bff\u547d\uff0c\u5b83\u5230\u4e86 B \u7aef\u540e\uff0cB \u7aef\u7531\u4e8e\u5173\u95ed\u8fde\u63a5\u4e86\uff0c\u4f1a\u54cd\u5e94 RST \u5305\uff0c\u8fd9\u4e2a RST \u5305\u6700\u957f\u4e5f\u4f1a\u5728 MSL \u65f6\u957f\u540e\u5230\u8fbe A\uff0c\u90a3\u4e48 A \u7aef\u53ea\u8981\u4fdd\u6301 TIME_WAIT \u5230\u8fbe 2MS \u5c31\u80fd\u4fdd\u8bc1\u7f51\u7edc\u4e2d\u8fd9\u4e2a\u8fde\u63a5\u7684\u5305\u90fd\u4f1a\u6d88\u5931\u3002
    \nMSL \u7684\u65f6\u957f\u88ab RFC \u5b9a\u4e49\u4e3a 2\u5206\u949f\uff0c\u4f46\u5728\u4e0d\u540c\u7684 unix \u5b9e\u73b0\u4e0a\uff0c\u8fd9\u4e2a\u503c\u4e0d\u5e76\u786e\u5b9a\uff0c\u6211\u4eec\u5e38\u7528\u7684 centOS \u4e0a\uff0c\u5b83\u88ab\u5b9a\u4e49\u4e3a 30s\uff0c\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7 \/proc\/sys\/net\/ipv4\/tcp_fin_timeout \u8fd9\u4e2a\u6587\u4ef6\u67e5\u770b\u548c\u4fee\u6539\u8fd9\u4e2a\u503c\u3002<\/p>\n<\/blockquote>\n<\/li>\n

  4. CLOSE_WAIT<\/a>
    \n CLOSE_WAIT\u662f\u88ab\u52a8\u5173\u95ed\u7684\u4e00\u65b9\u4ea7\u751f\u7684\uff0c\u4e00\u822c\u662fserver\u3002
    \n \u63a5\u6536\u5230\u5173\u95ed\u8fde\u63a5\u65f6\uff0c\u5728\u53d1\u51faACK\u7684\u540c\u65f6\uff0c\u544a\u77e5\u4e0a\u5c42\uff0c\u5e76\u7b49\u5f85\u4e0a\u5c42\u5904\u7406\u5b8c\u540e\u7684\u901a\u77e5\uff0c\u5728\u6b64\u671f\u95f4\u4fdd\u6301CLOSE_WAIT\u72b6\u6001\uff0c\u5728\u63a5\u6536\u5230\u4e0a\u5c42\u901a\u77e5\u540e\uff0c\u53d1\u9001FIN\uff0c\u5e76\u8fdb\u5165LAST_ACK\u72b6\u6001\u3002
    \n \u82e5\u5927\u91cf\u51fa\u73b0CLOSE_WAIT\uff0c\u53ef\u80fd\u662f\u7a0b\u5e8f\u54cd\u5e94\u6162\u3001\u4e0a\u5c42\u6ca1\u6709close\u8fde\u63a5\u7b49\u539f\u56e0\u3002<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"

    \u8fd9\u7bc7 TCP \u3001UDP \u7edd\u4e86\uff01 \u4f60\u8fd8\u5728\u4e3a TCP \u91cd\u4f20\u3001\u6ed1\u52a8\u7a97\u53e3\u3001\u6d41\u91cf\u63a7\u5236\u3001\u62e5\u585e\u63a7\u5236\u53d1\u6101\u5417\uff1f\u770b\u5b8c\u56fe\u89e3\u5c31\u4e0d\u6101\u4e86… TIME_WAIT  TIME_WAIT\u662f\u4e3b\u52a8\u5173\u95ed\u7684\u4e00\u65b9\u4ea7\u751f\u7684\uff0c\u4e00\u822c\u662fclient\u3002  TCP\u8fde\u63a5\u4e2d\uff0c\u4e3b\u52a8\u5173\u95ed\u7684\u4e00\u65b9\u5728\u5173\u95ed\u540e\u7684\u4e00\u6bb5\u65f6\u95f4\u5185\u4fdd\u6301\u4e00\u4e2aTIME_WAIT\u7684\u72b6\u6001\u3002  \u72b6\u6001\u7ef4\u6301\u65f6\u95f4\u4e00\u822c\u662f2MSL\uff08Maximum Segment Lifetime\uff0c\u6700\u5927\u5206\u6bb5\u5bff\u547d\uff09\uff0c\u4f5c\u7528\u6709\u4e24\u70b9\uff1a    \uff081\uff09\u4fdd\u8bc1\u8fde\u63a5\u6b63\u5e38\u7ec8\u6b62    \uff082\uff09\u4fdd\u8bc1\u7f51\u7edc\u4e2d\u672a\u63a5\u6536\u7684\u6570\u636e\u5305\u6b63\u5e38\u8fc7\u671f \u6458\u62841 \u6682\u4ee5 A\u3001B \u6765\u4ee3\u6307 TCP \u8fde\u63a5\u7684\u4e24\u7aef\uff0cA \u4e3a\u4e3b\u52a8\u5173\u95ed\u7684\u4e00\u7aef\u3002 1\u3001\u56db\u6b21\u6325\u624b\u4e2d\uff0cA \u53d1 FIN\uff0c B \u54cd\u5e94 ACK\uff0cB \u518d\u53d1 FIN\uff0cA \u54cd\u5e94 ACK \u5b9e\u73b0\u8fde\u63a5\u7684\u5173\u95ed\u3002\u800c\u5982\u679c A \u54cd\u5e94\u7684 ACK \u5305\u4e22\u5931\uff0cB \u4f1a\u4ee5\u4e3a A \u6ca1\u6709\u6536\u5230\u81ea\u5df1\u7684\u5173\u95ed\u8bf7\u6c42\uff0c\u7136\u540e\u4f1a\u91cd\u8bd5\u5411 A \u518d\u53d1 FIN \u5305\u3002 \u5982\u679c\u6ca1\u6709 TIME_WAIT \u72b6\u6001\uff0cA \u4e0d\u518d\u4fdd\u5b58\u8fd9\u4e2a\u8fde\u63a5\u7684\u4fe1\u606f\uff0c\u6536\u5230\u4e00\u4e2a\u4e0d\u5b58\u5728\u7684\u8fde\u63a5\u7684\u5305\uff0cA \u4f1a\u54cd\u5e94 RST \u5305\uff0c\u5bfc\u81f4 B \u7aef\u5f02\u5e38\u54cd\u5e94\u3002 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[7],"tags":[],"_links":{"self":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts\/237"}],"collection":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=237"}],"version-history":[{"count":2,"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts\/237\/revisions"}],"predecessor-version":[{"id":242,"href":"http:\/\/47.103.123.166\/index.php?rest_route=\/wp\/v2\/posts\/237\/revisions\/242"}],"wp:attachment":[{"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=237"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=237"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/47.103.123.166\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=237"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}