{"id":5017,"date":"2021-01-31T13:52:56","date_gmt":"2021-01-31T05:52:56","guid":{"rendered":"https:\/\/damogame.cn\/wordpress\/?p=5017"},"modified":"2021-01-31T13:53:18","modified_gmt":"2021-01-31T05:53:18","slug":"%e6%9c%8d%e5%8a%a1%e5%99%a8http%e8%bf%9e%e6%8e%a5%e5%87%ba%e7%8e%b0%e5%a4%a7%e9%87%8ftime_wait%e9%97%ae%e9%a2%98%e7%9a%84%e8%a7%a3%e5%86%b3%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/5017","title":{"rendered":"\u670d\u52a1\u5668http\u8fde\u63a5\u51fa\u73b0\u5927\u91cfTIME_WAIT\u95ee\u9898\u7684\u89e3\u51b3\u65b9\u6cd5"},"content":{"rendered":"
\n
\n
\n

\u539f\u6587\u5730\u5740<\/a><\/p>\n<\/div>\n

\n<\/div>\n<\/div>\n

\n
\n
\n
\n

 <\/p>\n

\u6700\u8fd1\u7528\u6237\u7684tomcat\u670d\u52a1\u5668\u4e0a\u51fa\u73b0\u5927\u91cfTIME_WAIT\u00a0\u72b6\u6001\u7684\u8fde\u63a5\uff0c\u5bfc\u81f4\u540e\u9762\u7684\u8fde\u63a5\u8fdb\u4e0d\u53bb\uff0c\u51fa\u73b0\u670d\u52a1\u6ca1\u6709\u54cd\u5e94\u7684\u60c5\u51b5\u3002<\/p>\n

\u9996\u5148\u4f7f\u7528\u547d\u4ee4\u67e5\u770b\u5f53\u524d\u7684\u5404\u79cd\u72b6\u6001\u7684\u6570\u91cf\uff1a<\/p>\n

netstat\u00a0-n\u00a0|\u00a0awk\u00a0‘\/^tcp\/\u00a0{++S[$NF]}\u00a0END\u00a0{for(a\u00a0in\u00a0S)\u00a0print\u00a0a,\u00a0S[a]}’<\/p>\n

\u6267\u884c\u540e\uff0c\u4e00\u822c\u7ed3\u679c\u5982\u4e0b\uff1a<\/p>\n

TIME_WAIT 8<\/p>\n

CLOSE_WAIT 323<\/p>\n

SYN_SENT 1<\/p>\n

ESTABLISHED 6171<\/p>\n

\u5176\u4e2d\u5e38\u7528\u7684\u4e09\u4e2a\u72b6\u6001\u662f\uff1a<\/p>\n

ESTABLISHED \u00a0 \u00a0 \u00a0\u8868\u793a\u6b63\u5728\u901a\u4fe1<\/p>\n

TIME_WAIT \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u8868\u793a\u4e3b\u52a8\u5173\u95ed<\/p>\n

CLOSE_WAIT \u00a0 \u00a0 \u00a0 \u00a0\u8868\u793a\u88ab\u52a8\u5173\u95ed<\/p>\n

 <\/p>\n

1.\u51fa\u73b0TIME_WAIT\u7684\u539f\u56e0<\/strong><\/p>\n

TCP\u5efa\u7acb\u4e00\u4e2a\u8fde\u63a5\u81f3\u5c11\u9700\u8981\u4ea4\u6362\u4e09\u4e2a\u5206\u7ec4\uff0c\u4e5f\u56e0\u6b64\u79f0\u4e4b\u4e3aTCP\u7684\u4e09\u8def\u63e1\u624b\uff08three-way handshake\uff09\uff0c\u7136\u800c\u5728TCP\u7ec8\u6b62\u8fde\u63a5\u65f6\uff0c\u7531\u4e8e\u53cc\u65b9\u90fd\u9700\u8981\u53d1\u9001\u4e00\u4e2aFIN\u5206\u8282\u7ed9\u5bf9\u7aef\u786e\u8ba4\uff0c\u56e0\u6b64TCP\u7ec8\u6b62\u8fde\u63a5\u4e00\u822c\u662f\u9700\u8981\u4ea4\u6362\u56db\u4e2a\u5206\u8282\u3002\u5177\u4f53\u6765\u770b\uff1a
\n1\uff09 \u5e94\u7528\u8fdb\u7a0b\uff08active close\uff09\u9996\u5148\u8c03\u7528close\uff0c\u4e8e\u662f\u5bfc\u81f4TCP\u53d1\u9001\u4e00\u4e2aFIN\u5206\u8282\uff0c\u8868\u793a\u6570\u636e\u5df2\u5206\u9001\u5b8c\u6bd5\uff0c\u8bf7\u6c42\u5173\u95ed\u5957\u63a5\u5b57\u3002
\n2\uff09 \u53e6\u4e00\u7aef\u5e94\u7528\u8fdb\u7a0b\uff08passive close\uff09\u63a5\u53d7\u6536\u5230FIN\uff0c\u5e76\u7531\u8be5\u7aef\u7684TCP\u786e\u8ba4\uff08\u786e\u8ba4\u7684\u8fc7\u7a0b\u662fTCP\u53d1\u9001ACK\u5206\u8282\u7ed9\u5bf9\u7aef\u5957\u63a5\u5b57\uff09\u3002FIN\u7684\u63a5\u53d7\u4e5f\u4f5c\u4e3a\u6587\u4ef6\u7ed3\u675f\u7b26\u4f20\u9012\u7ed9\u4e0a\u5c42\u5e94\u7528\u8fdb\u7a0b\u3002\u8fd9\u91cc\u7684\u6587\u4ef6\u7ed3\u675f\u7b26\u5e76\u975e\u5e94\u7528\u8fdb\u7a0b\u7684EOF\uff0c\u5728TCP\u5b57\u8282\u6d41\u4e2d\uff0cEOF\u7684\u8bfb\u6216\u5199\u901a\u8fc7\u6536\u53d1\u4e00\u4e2a\u7279\u6b8a\u7684FIN\u5206\u8282\u6765\u5b9e\u73b0\u3002
\n3\uff09 \u53e6\u7aef\uff08passive close\uff09\u5e94\u7528\u8fdb\u7a0b\u5728\u63a5\u53d7\u5230\u6587\u4ef6\u675f\u7b26\u540e\uff0c\u4f1a\u8c03\u7528close\u5173\u95ed\u5b83\u7684\u5957\u63a5\u5b57\uff0c\u8fd9\u5bfc\u81f4\u8be5\u7aef\u7684TCP\u4e5f\u53d1\u9001\u4e86\u4e00\u4e2aFIN\u5206\u8282\u3002
\n4\uff09 \u4e3b\u52a8\u5173\u95ed\u7aef\uff08active close\uff09\u63a5\u53d7\u5230\u8fd9\u4e2aFIN\u540e\uff0cTCP\u5bf9\u5b83\u8fdb\u884c\u786e\u8ba4\u3002\uff08TCP\u53d1\u9001ACK\u5206\u8282\uff0c\u503c\u5f97\u6ce8\u610f\u7684\u662f\u4e3b\u52a8\u5173\u95ed\u7aef\u5728\u672a\u63a5\u53d7\u5230FIN\u4e4b\u524d\uff0c\u5b83\u7684\u72b6\u6001\u5c31\u662fTIME_WAIT\uff09\u3002<\/p>\n

\"\"<\/p>\n

TIME_OUT\u72b6\u6001\u7684\u5b58\u5728\u7684\u610f\u4e49<\/strong>
\n\u4ece\u56fe\u4e2d\uff0c\u5f88\u6e05\u6670\u7684\u770b\u5230TIME_WAIT\u72b6\u6001\u53d1\u751f\u5728\u4e86active close \u7aef\uff0c\u4ea7\u751f\u7684\u65f6\u95f4\u70b9\u662f\u53d1\u9001ACK K+1 \u5206\u8282\u4e4b\u540e\uff0c\u539f\u56e0\u662f\u9632\u6b62ACK\u5206\u8282\u5728\u7f51\u7edc\u4e2d\u4e22\u5931\uff08lost\uff09\uff0c\u6b64\u65f6passive close\u8fdb\u5165LAST_ACK\u72b6\u6001\uff0c\u610f\u4e3a\u7b49\u5f85ACK\u5206\u8282\uff0c\u5982\u679c\u6b64\u65f6ACK\u5206\u8282\u771f\u7684\u4e22\u5931\u4e86\uff08passive close\u7aef\u7684LAST_ACK\u8d85\u65f6\uff09\uff0c\u90a3\u4e48passive close\u7aef\u5c06\u4f1a\u518d\u6b21\u53d1\u9001\u4e00\u4e2aFIN K\u5206\u8282\u7ed9\u5bf9\u7aef\u3002\u8fd9\u5c31\u662f\u4e3a\u4ec0\u4e48\u5728\u56fe\u4e2d\uff0c\u51fa\u73b0\u4e24\u6b21FIN\u7684\u5206\u8282\u3002<\/p>\n

\u5bf9\u4e8e\u57fa\u4e8eTCP\u7684HTTP\u534f\u8bae\uff0c\u5173\u95edTCP\u8fde\u63a5\u7684\u662fServer\u7aef\uff0c\u8fd9\u6837\uff0cServer\u7aef\u4f1a\u8fdb\u5165TIME_WAIT\u72b6\u6001\uff0c\u53ef\u00a0\u60f3\u800c\u77e5\uff0c\u5bf9\u4e8e\u8bbf \u95ee\u91cf\u5927\u7684Web\u00a0Server\uff0c\u4f1a\u5b58\u5728\u5927\u91cf\u7684TIME_WAIT\u72b6\u6001\uff0c\u5047\u5982server\u4e00\u79d2\u949f\u63a5\u65361000\u4e2a\u8bf7\u6c42\uff0c\u90a3\u4e48\u5c31\u4f1a\u79ef\u538b 240*1000=240\uff0c000\u4e2a\u00a0TIME_WAIT\u7684\u8bb0\u5f55\uff0c\u7ef4\u62a4\u8fd9\u4e9b\u72b6\u6001\u7ed9Server\u5e26\u6765\u8d1f\u62c5\u3002\u5f53\u7136\u73b0\u4ee3\u64cd\u4f5c\u7cfb\u7edf\u90fd\u4f1a\u7528\u5feb\u901f\u7684\u67e5\u627e\u7b97\u6cd5\u6765\u7ba1\u7406\u8fd9\u4e9b TIME_WAIT\uff0c\u6240\u4ee5\u5bf9\u4e8e\u65b0\u7684\u00a0TCP\u8fde\u63a5\u8bf7\u6c42\uff0c\u5224\u65ad\u662f\u5426hit\u4e2d\u4e00\u4e2aTIME_WAIT\u4e0d\u4f1a\u592a\u8d39\u65f6\u95f4\uff0c\u4f46\u662f\u6709\u8fd9\u4e48\u591a\u72b6\u6001\u8981\u7ef4\u62a4\u603b\u662f\u4e0d\u597d\u3002<\/p>\n

 <\/p>\n

2.\u89e3\u51b3\u51fa\u73b0\u5927\u91cfTIME_WAIT\u60c5\u51b5\u7684\u65b9\u6cd5<\/strong><\/p>\n

\u5bf9\/etc\/sysctl.conf\u6587\u4ef6\u8fdb\u884c\u4fee\u6539\uff1a<\/p>\n

<\/code><\/pre>\n
    \n
  1. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u5bf9\u4e8e\u4e00\u4e2a\u65b0\u5efa\u8fde\u63a5\uff0c\u5185\u6838\u8981\u53d1\u9001\u591a\u5c11\u4e2a SYN \u8fde\u63a5\u8bf7\u6c42\u624d\u51b3\u5b9a\u653e\u5f03,\u4e0d\u5e94\u8be5\u5927\u4e8e255\uff0c\u9ed8\u8ba4\u503c\u662f5\uff0c\u5bf9\u5e94\u4e8e180\u79d2\u5de6\u53f3\u65f6\u95f4 <\/span><\/div>\n<\/div>\n<\/li>\n
  2. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_syn_retries=2<\/span><\/div>\n<\/div>\n<\/li>\n
  3. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #net.ipv4.tcp_synack_retries=2 <\/span><\/div>\n<\/div>\n<\/li>\n
  4. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u8868\u793a\u5f53keepalive\u8d77\u7528\u7684\u65f6\u5019\uff0cTCP\u53d1\u9001keepalive\u6d88\u606f\u7684\u9891\u5ea6\u3002\u7f3a\u7701\u662f2\u5c0f\u65f6\uff0c\u6539\u4e3a300\u79d2 <\/span><\/div>\n<\/div>\n<\/li>\n
  5. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_keepalive_time=1200<\/span><\/div>\n<\/div>\n<\/li>\n
  6. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_orphan_retries=3<\/span><\/div>\n<\/div>\n<\/li>\n
  7. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u8868\u793a\u5982\u679c\u5957\u63a5\u5b57\u7531\u672c\u7aef\u8981\u6c42\u5173\u95ed\uff0c\u8fd9\u4e2a\u53c2\u6570\u51b3\u5b9a\u4e86\u5b83\u4fdd\u6301\u5728FIN-WAIT-2\u72b6\u6001\u7684\u65f6\u95f4 <\/span><\/div>\n<\/div>\n<\/li>\n
  8. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_fin_timeout=30<\/span><\/div>\n<\/div>\n<\/li>\n
  9. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u8868\u793aSYN\u961f\u5217\u7684\u957f\u5ea6\uff0c\u9ed8\u8ba4\u4e3a1024\uff0c\u52a0\u5927\u961f\u5217\u957f\u5ea6\u4e3a8192\uff0c\u53ef\u4ee5\u5bb9\u7eb3\u66f4\u591a\u7b49\u5f85\u8fde\u63a5\u7684\u7f51\u7edc\u8fde\u63a5\u6570\u3002 <\/span><\/div>\n<\/div>\n<\/li>\n
  10. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_max_syn_backlog = 4096<\/span><\/div>\n<\/div>\n<\/li>\n
  11. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u8868\u793a\u5f00\u542fSYN Cookies\u3002\u5f53\u51fa\u73b0SYN\u7b49\u5f85\u961f\u5217\u6ea2\u51fa\u65f6\uff0c\u542f\u7528cookies\u6765\u5904\u7406\uff0c\u53ef\u9632\u8303\u5c11\u91cfSYN\u653b\u51fb\uff0c\u9ed8\u8ba4\u4e3a0\uff0c\u8868\u793a\u5173\u95ed <\/span><\/div>\n<\/div>\n<\/li>\n
  12. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_syncookies = 1<\/span><\/div>\n<\/div>\n<\/li>\n
  13. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  14. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u8868\u793a\u5f00\u542f\u91cd\u7528\u3002\u5141\u8bb8\u5c06TIME-WAIT sockets\u91cd\u65b0\u7528\u4e8e\u65b0\u7684TCP\u8fde\u63a5\uff0c\u9ed8\u8ba4\u4e3a0\uff0c\u8868\u793a\u5173\u95ed <\/span><\/div>\n<\/div>\n<\/li>\n
  15. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_tw_reuse = 1<\/span><\/div>\n<\/div>\n<\/li>\n
  16. \n
    \n
    <\/div>\n<\/div>\n
    \n
    #\u8868\u793a\u5f00\u542fTCP\u8fde\u63a5\u4e2dTIME-WAIT sockets\u7684\u5feb\u901f\u56de\u6536\uff0c\u9ed8\u8ba4\u4e3a0\uff0c\u8868\u793a\u5173\u95ed <\/span><\/div>\n<\/div>\n<\/li>\n
  17. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_tw_recycle = 1<\/span><\/div>\n<\/div>\n<\/li>\n
  18. \n
    \n
    <\/div>\n<\/div>\n
    \n
    <\/div>\n<\/div>\n<\/li>\n
  19. \n
    \n
    <\/div>\n<\/div>\n
    \n
    ##\u51cf\u5c11\u8d85\u65f6\u524d\u7684\u63a2\u6d4b\u6b21\u6570 <\/span><\/div>\n<\/div>\n<\/li>\n
  20. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.ipv4.tcp_keepalive_probes=5<\/span><\/div>\n<\/div>\n<\/li>\n
  21. \n
    \n
    <\/div>\n<\/div>\n
    \n
    ##\u4f18\u5316\u7f51\u7edc\u8bbe\u5907\u63a5\u6536\u961f\u5217 <\/span><\/div>\n<\/div>\n<\/li>\n
  22. \n
    \n
    <\/div>\n<\/div>\n
    \n
    net.core.netdev_max_backlog=3000<\/span><\/div>\n<\/div>\n<\/li>\n<\/ol>\n
    <\/code><\/pre>\n
    \u4fee\u6539\u5b8c\u4e4b\u540e\uff0c\u6267\u884c\uff1a<\/p>\n
    \/sbin\/sysctl -p<\/p>\n
    \u8fd9\u6837\u53c2\u6570\u5c31\u80fd\u751f\u6548\u4e86\u3002<\/p>\n
    \u4e0a\u9762\u4fee\u6539\u7684\u53c2\u6570\u91cc\u9762\uff0c\u6700\u4e3b\u8981\u7684\u662f4\u4e2a\u53c2\u6570\uff1a<\/p>\n
    net.ipv4.tcp_tw_reuse<\/p>\n
    net.ipv4.tcp_tw_recycle<\/p>\n
    net.ipv4.tcp_fin_timeout
    \nnet.ipv4.tcp_keepalive_*<\/div>\n
    \u4e00\u822c\u60c5\u51b5\u4e0b\uff0c\u4fee\u6539\u8fd9\u4e9b\u57fa\u672c\u4e0a\u5c31\u591f\u7528\u4e86\u3002<\/div>\n
     <\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/article>\n","protected":false},"excerpt":{"rendered":"
    \u539f\u6587\u5730\u5740   \u6700\u8fd1\u7528\u6237\u7684tom<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[],"tags":[118],"class_list":["post-5017","post","type-post","status-publish","format-standard","hentry","tag-02-"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/5017","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=5017"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/5017\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=5017"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=5017"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=5017"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}