{"id":31497,"date":"2021-02-09T21:53:16","date_gmt":"2021-02-09T13:53:16","guid":{"rendered":"https:\/\/web.mwwsb.com.my\/pjci\/?post_type=kb&#038;p=31497"},"modified":"2022-09-07T19:54:47","modified_gmt":"2022-09-07T11:54:47","slug":"how-to-allow-port-26-for-smtp-in-iptables","status":"publish","type":"kb","link":"https:\/\/www.casbay.com\/guide\/kb\/how-to-allow-port-26-for-smtp-in-iptables","title":{"rendered":"HOW TO: Allow Port 26 for SMTP in IPtables"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"31497\" class=\"elementor elementor-31497\" data-elementor-post-type=\"kb\">\n\t\t\t\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-d259f58 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"d259f58\" data-element_type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-7bc8f0e\" data-id=\"7bc8f0e\" data-element_type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t\t\t<div class=\"elementor-element elementor-element-8ac69db elementor-widget elementor-widget-heading\" data-id=\"8ac69db\" data-element_type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">HOW TO: Allow Port 26 for SMTP in IPtables<\/h2>\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-1945e96 elementor-widget elementor-widget-text-editor\" data-id=\"1945e96\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>Please take note that Malaysia and in some countries, or better said some ISPs are now blocking SMTP. Port 25 to mitigate Spam in their network.<\/p><p>An approach lots of systems administrators are taking is to use port 26, so you can configure your email client and your colleagues. Email\u2019s clients to use port 26 instead of 25 to send emails.<\/p><p>Here I will show you how to configure your smtp server to accept email connections on port 26, independent of the server you are using, <a href=\"http:\/\/www.postfix.org\/\" rel=\"noopener\">Postfix<\/a>, or Sendmail or any other server. First you need to open port 26, to do so, insert this line in your firewall configuration.<\/p><p><strong>iptables -A INPUT -p tcp \u2013dport 26 -j ACCEPT<\/strong><\/p><p>This will enable the server to accept connections on port 26, from all over the world, next redirect the connections on port 26 to 25, this way you do not need to reconfigure your email server to listen on port 26.<\/p><p><strong>iptables -A PREROUTING -t nat -p tcp \u2013dport 26 -j REDIRECT \u2013to-port 25<\/strong><\/p><p>With these two line you will make your email server to accept emails on port 26.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-bff5a38 elementor-widget elementor-widget-text-editor\" data-id=\"bff5a38\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<p>Check out next article on <a href=\"https:\/\/www.casbay.com\/guide\/kb\/enable-root-login-via-ssh\/\">How to Check if IP is blocked from IPtables<\/a>.<\/p>\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>HOW TO: Allow Port 26 for SMTP in IPtables Please take note that Malaysia and in some countries, or better said some ISPs are now blocking SMTP. Port 25 to mitigate Spam in their network. An approach lots of systems administrators are taking is to use port 26, so you can configure your email client [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"no-sidebar","site-content-layout":"page-builder","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"disabled","ast-breadcrumbs-content":"","ast-featured-img":"disabled","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}}},"kbtopic":[110],"kbtag":[106,105],"mkb_version":[],"_links":{"self":[{"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/kb\/31497"}],"collection":[{"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/kb"}],"about":[{"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/types\/kb"}],"author":[{"embeddable":true,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/comments?post=31497"}],"version-history":[{"count":15,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/kb\/31497\/revisions"}],"predecessor-version":[{"id":38112,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/kb\/31497\/revisions\/38112"}],"wp:attachment":[{"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/media?parent=31497"}],"wp:term":[{"taxonomy":"kbtopic","embeddable":true,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/kbtopic?post=31497"},{"taxonomy":"kbtag","embeddable":true,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/kbtag?post=31497"},{"taxonomy":"mkb_version","embeddable":true,"href":"https:\/\/www.casbay.com\/guide\/wp-json\/wp\/v2\/mkb_version?post=31497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}