{"id":4615,"date":"2015-04-26T19:21:36","date_gmt":"2015-04-26T11:21:36","guid":{"rendered":"http:\/\/rmohan.com\/?p=4615"},"modified":"2015-04-26T19:21:36","modified_gmt":"2015-04-26T11:21:36","slug":"disable-ipv6-lookups-with-bind-on-rhel-or-centos","status":"publish","type":"post","link":"https:\/\/mohan.sg\/?p=4615","title":{"rendered":"Disable IPv6 lookups with Bind on RHEL or CentOS"},"content":{"rendered":"<p>Discovered during a recent project. Bind \/ Named was constantly spamming the logs about it being unable to reach root servers. The logs revealed that we were talking IPv6 addresses. Which was assumed to be disabled.<\/p>\n<p>The less cool part was that in \u201c\/etc\/named.conf\u201d the following was commented out.<\/p>\n<pre>\/\/      listen-on-v6 port 53 { ::1; };<\/pre>\n<p>It turns out that <strong>to disable<\/strong> the IPv6 lookups you have to edit \u201c\/etc\/sysconfig\/named\u201d and set<\/p>\n<pre>OPTIONS=\"-4\"<\/pre>\n<p>The option does the following<\/p>\n<blockquote><p>Use IPv4 only even if the host machine is capable of IPv6. -4 and -6 are mutually exclusive.<\/p><\/blockquote>\n<p>You then run<\/p>\n<pre>service named restart<\/pre>\n<p>This serves the very practical purpose of not spamming the logs. My ISP has yet to enable IPv6 so it does me no good.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Discovered during a recent project. Bind \/ Named was constantly spamming the logs about it being unable to reach root servers. The logs revealed that we were talking IPv6 addresses. Which was assumed to be disabled.<\/p>\n<p>The less cool part was that in \u201c\/etc\/named.conf\u201d the following was commented out.<\/p>\n<p> \/\/ listen-on-v6 port 53 { ::1; [&#8230;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5,4,29],"tags":[],"_links":{"self":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/4615"}],"collection":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=4615"}],"version-history":[{"count":1,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/4615\/revisions"}],"predecessor-version":[{"id":4616,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/4615\/revisions\/4616"}],"wp:attachment":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=4615"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=4615"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=4615"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}