{"id":1527,"date":"2018-10-15T21:03:36","date_gmt":"2018-10-15T13:03:36","guid":{"rendered":"http:\/\/www.eumz.com\/?p=1527"},"modified":"2018-10-15T21:03:36","modified_gmt":"2018-10-15T13:03:36","slug":"linux%e7%b3%bb%e7%bb%9ftcpdump%e4%b8%a2%e5%8c%85%e9%97%ae%e9%a2%98%e8%a7%a3%e5%86%b3%e6%96%b9%e6%b3%95","status":"publish","type":"post","link":"https:\/\/www.wxcn.com\/?p=1527","title":{"rendered":"linux\u7cfb\u7edftcpdump\u4e22\u5305\u95ee\u9898\u89e3\u51b3\u65b9\u6cd5"},"content":{"rendered":"\n<p>\u5728\u4e00\u53f0suse linux\u4e0a\u4f7f\u7528tcpdump\u547d\u4ee4\u6293\u5305\uff0c\u51fa\u73b0\u201cpackets dropped by kernel\u201d\uff0c\u4e00\u822c\u9020\u6210\u8fd9\u79cd\u4e22\u5305\u7684\u539f\u56e0\u662flibcap\u6293\u5230\u5305\u540e\uff0ctcpdump\u4e0a\u5c42\u6ca1\u6709\u53ca\u65f6\u53d6\u51fa\uff0c\u5bfc\u81f4libcap\u7f13\u51b2\u533a\u6ea2\u51fa\uff0c\u4ece\u800c\u8986\u76d6\u4e86\u672a\u5904\u7406\u5305\uff0c\u663e\u793a\u4e3adropped by kernel\uff0c\u8fd9\u91cc\u7684kernel\u5e76\u4e0d\u662f\u8bf4\u662f\u88ablinux\u5185\u6838\u629b\u5f03\u7684\uff0c\u800c\u662f\u88abtcpdump\u7684\u5185\u6838\uff0c\u5373libcap\u629b\u5f03\u6389\u3002<br>\u89e3\u51b3\u65b9\u6cd5\uff1a<\/p>\n\n\n\n<p>\u6839\u636e\u4ee5\u4e0a\u5206\u6790\uff0c\u53ef\u4ee5\u901a\u8fc7\u6539\u5584tcpdump\u4e0a\u5c42\u7684\u5904\u7406\u6548\u7387\u6765\u51cf\u5c11\u4e22\u5305\u7387\uff0c\u4e0b\u9762\u7684\u51e0\u6b65\u6839\u636e\u9700\u8981\u9009\u7528\uff0c\u6bcf\u4e00\u6b65\u90fd\u80fd\u51cf\u5c11\u4e00\u5b9a\u7684\u4e22\u5305\u7387\u3002<\/p>\n\n\n\n<p>1.\u6700\u5c0f\u5316\u6293\u53d6\u8fc7\u6ee4\u8303\u56f4\uff0c\u5373\u901a\u8fc7\u6307\u5b9a\u7f51\u5361\uff0c\u7aef\u53e3\uff0c\u5305\u6d41\u5411\uff0c\u5305\u5927\u5c0f\u51cf\u5c11\u5305\u6570\u91cf<\/p>\n\n\n\n<p>2. \u6dfb\u52a0-n\u53c2\u6570\uff0c\u7981\u6b62\u53cd\u5411\u57df\u540d\u89e3\u6790<br>tcpdump -i eth0 dst port 1234 and udp -s 2048 -n -X -tt &gt;a.pack<br>\u5927\u591a\u6570\u60c5\u51b5\u8fd9\u6837\u5c31\u53ef\u4ee5\u89e3\u51b3<br>\u53ef\u4ee5\u901a\u8fc7\u6539\u5584tcpdump\u4e0a\u5c42\u7684\u5904\u7406\u6548\u7387\u6765\u51cf\u5c11\u4e22\u5305\u7387<\/p>\n\n\n\n<p>3. \u5c06\u6570\u636e\u5305\u8f93\u51fa\u5230cap\u6587\u4ef6<br>tcpdump -i eth0 dst port 1234 and udp -s 2048 -n -X -tt -w a.cap<\/p>\n\n\n\n<p>4. \u7528sysctl\u4fee\u6539SO_REVBUF\u53c2\u6570\uff0c\u589e\u52a0libcap\u7f13\u51b2\u533a\u957f\u5ea6<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5728\u4e00\u53f0suse linux\u4e0a\u4f7f\u7528tcpdump\u547d\u4ee4\u6293\u5305\uff0c\u51fa\u73b0\u201cpackets dropped by kerne [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[180,183,285],"class_list":["post-1527","post","type-post","status-publish","format-standard","hentry","category-operating-system","tag-kernel","tag-linux-2","tag-tcpdump"],"_links":{"self":[{"href":"https:\/\/www.wxcn.com\/index.php?rest_route=\/wp\/v2\/posts\/1527","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wxcn.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wxcn.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wxcn.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wxcn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1527"}],"version-history":[{"count":0,"href":"https:\/\/www.wxcn.com\/index.php?rest_route=\/wp\/v2\/posts\/1527\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.wxcn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1527"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wxcn.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1527"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wxcn.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1527"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}