{"id":502,"date":"2010-07-15T11:36:14","date_gmt":"2010-07-15T11:36:14","guid":{"rendered":"http:\/\/wiki.freeiz.com\/?p=502"},"modified":"2016-08-09T12:02:13","modified_gmt":"2016-08-09T12:02:13","slug":"linux-iptables-output-chain","status":"publish","type":"post","link":"https:\/\/wiki-see.info\/wp\/2010\/07\/15\/linux-iptables-output-chain\/","title":{"rendered":"Linux Iptables Output Chain"},"content":{"rendered":"<p><!-- ======================================================= --> <!-- Created by AbiWord, a free, Open Source wordprocessor.  --> <!-- For more information visit http:\/\/www.abisource.com.    --> <!-- ======================================================= --> <!-- #toc, .toc, .mw-warning { \tborder: 1px solid #aaa; \tbackground-color: #f9f9f9; \tpadding: 5px; \tfont-size: 95%; } #toc h2, .toc h2 { \tdisplay: inline; \tborder: none; \tpadding: 0; \tfont-size: 100%; \tfont-weight: bold; } #toc #toctitle, .toc #toctitle, #toc .toctitle, .toc .toctitle { \ttext-align: center; } #toc ul, .toc ul { \tlist-style-type: none; \tlist-style-image: none; \tmargin-left: 0; \tpadding-left: 0; \ttext-align: left; } #toc ul ul, .toc ul ul { \tmargin: 0 0 0 2em; } #toc .toctoggle, .toc .toctoggle { \tfont-size: 94%; }@media print, projection, embossed { \tbody { \t\tpadding-top:1in; \t\tpadding-bottom:1in; \t\tpadding-left:1in; \t\tpadding-right:1in; \t} } body { \tfont-family:'Times New Roman'; \tcolor:#000000; \twidows:2; \tfont-style:normal; \ttext-indent:0in; \tfont-variant:normal; \tfont-weight:normal; \tfont-size:12pt; \ttext-decoration:none; \ttext-align:left; } table { } td { \tborder-collapse:collapse; \ttext-align:left; \tvertical-align:top; } p, h1, h2, h3, li { \tcolor:#000000; \tfont-family:'Times New Roman'; \tfont-size:12pt; \ttext-align:left; \tvertical-align:normal; } --><\/p>\n<div>\n<p dir=\"ltr\">sudo iptables -I smtp_out\u00a01 -p tcp -s 10.11.254.250 -d 0.0.0.0\/0 &#8211;dport 25 -j ACCEPT<br \/>\nsudo iptables -I\u00a0smtp_out 2 -p tcp -s 10.11.254.251 -d 0.0.0.0\/0 &#8211;dport 25 -j ACCEPT<br \/>\nsudo iptables -I smtp_out 4 -p tcp -s 0.0.0.0\/0 -d 0.0.0.0\/0 &#8211;dport 25 -j LOG<br \/>\nsudo iptables -I smtp_out 4 -p tcp -s 0.0.0.0\/0 -d 0.0.0.0\/0 &#8211;dport 25 -j DROP<\/p>\n<p dir=\"ltr\">The below statement will log all deny traffic which needs to be entered before the deny statement.<\/p>\n<p>sudo iptables -I smtp_out 4 -p tcp -s 0.0.0.0\/0 -d 0.0.0.0\/0 &#8211;dport 25 -j LOG<\/p>\n<p>Run this command to see log messages:<\/p>\n<p>sudo cat \/var\/log\/messages | grep DST=25<br \/>\nsudo cat \/var\/log\/messages | grep 217.154.157.250<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>sudo iptables -I smtp_out\u00a01 -p tcp -s 10.11.254.250 -d 0.0.0.0\/0 &#8211;dport 25 -j ACCEPT sudo iptables -I\u00a0smtp_out 2 -p tcp -s 10.11.254.251 -d 0.0.0.0\/0 &#8211;dport 25 -j ACCEPT sudo iptables -I smtp_out 4 -p tcp -s 0.0.0.0\/0 -d 0.0.0.0\/0 &#8211;dport 25 -j LOG sudo iptables -I smtp_out 4 -p tcp -s 0.0.0.0\/0 -d 0.0.0.0\/0 &#8211;dport [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[18],"tags":[393,423,529],"class_list":["post-502","post","type-post","status-publish","format-standard","hentry","category-iptables-linux","tag-iptables","tag-linux","tag-output-chain"],"_links":{"self":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts\/502","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/comments?post=502"}],"version-history":[{"count":1,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts\/502\/revisions"}],"predecessor-version":[{"id":4740,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/posts\/502\/revisions\/4740"}],"wp:attachment":[{"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/media?parent=502"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/categories?post=502"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wiki-see.info\/wp\/wp-json\/wp\/v2\/tags?post=502"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}