{"id":15026,"date":"2017-05-15T13:38:04","date_gmt":"2017-05-15T08:08:04","guid":{"rendered":"https:\/\/www.wikitechy.com\/technology\/?p=15026"},"modified":"2017-05-15T13:38:04","modified_gmt":"2017-05-15T08:08:04","slug":"flush-dns-cache-linux","status":"publish","type":"post","link":"https:\/\/www.wikitechy.com\/technology\/flush-dns-cache-linux\/","title":{"rendered":"How to Flush DNS Cache in Linux"},"content":{"rendered":"

DNS, or a Domain Name System, is responsible for resolving website names into their separate IP addresses. So, if you\u2019re having trouble connecting to a website, or if you just want a DNS change to be seen by your Ubuntu machine, you should try to flush the DNS cache. You can likewise clear DNS store in Ubuntu on the off chance that you rolled out improvements to the hosts document, and you need it to be “seen” by your framework without rebooting it.\u00a0 Well, if you\u2019re in any of these situations, and you want to clear DNS cache, here is the means by which to flush DNS store in Linux:<\/p>\n[ad type=”banner”]\n

Note<\/u><\/strong>:\u00a0<\/strong>I\u2019m using an Ubuntu 16.10 \u201cYakkety Yak\u201d system to demonstrate\u00a0these methods. However, the process should be similar on most Linux distros.<\/em><\/p>\n

\u00a0<\/em>Checking if DNS Caching is Enabled:<\/strong><\/span><\/p>\n

All Linux distros don’t carry on a similar way, with regards to things like storing DNS. For instance, Ubuntu, by default, doesn’t reserve DNS. Earlier we attempt to clear DNS cache on a Linux machine, let\u2019s check if caching is even enabled. To do this on an Ubuntu system, you can follow the steps below:<\/p>\n

    \n
  1. \u00a0Launch Terminal, and type \u201cps ax | grep dnsmasq<\/strong>\u201c.<\/li>\n<\/ol>\n

    \"<\/p>\n

      \n
    1. In the output from the command, you will be able to see a field called \u201ccache-size<\/strong>\u201c. Check its value.If the value is zero, it means that caching is disabled<\/strong>\u00a0on the system.<\/li>\n<\/ol>\n

      \"\"<\/p>\n

       <\/p>\n

      Note<\/u><\/strong>:<\/strong>\u00a0If you want to enable DNS caching on Linux, you can do so by using the command \u201csudo dnsmasq -c 150\u201d. You can use any number in place of 150, which is basically the number of entries that dnsmasq can cache.<\/em><\/p>\n

      \u00a0<\/strong>Flush DNS Cache in Ubuntu:<\/strong><\/span><\/p>\n

      If your Linux system is caching DNS entries, then you can try to flush the DNS cache in order to get rid of any DNS related problems. To clear DNS cache in Ubuntu, you can follow the steps below:<\/p>\n

        \n
      1. Launch Terminal (ctrl + alt + T), and type \u201csudo \/etc\/init.d\/dns-clean restart<\/strong>\u201c.<\/li>\n<\/ol>\n

        \"How<\/p>\n

          \n
        1. Next, type the command \u201csudo \/etc\/init.d\/networking force-reload<\/strong>\u201d<\/li>\n<\/ol>\n

          \"How<\/p>\n[ad type=”banner”]\n

          This will clear your DNS cache in Ubuntu, and if the problems you were experiencing were due to DNS issues, they should now be gone.<\/p>\n

          \u00a0Flush DNS Cache in DNS Services on Linux:<\/span><\/strong><\/h4>\n

          Alike I said, Ubuntu doesn\u2019t cache DNS entries by default, however, if you have manually installed a DNS service such as nscd, you can clear its cache. Methods to clear cache for some common DNS services are given below:<\/p>\n

          Flush nscd DNS Cache<\/strong><\/span><\/h4>\n
            \n
          • sudo \/etc\/init.d\/nscd restart<\/li>\n<\/ul>\n

            \"How<\/p>\n

            Flush dnsmasq DNS Cache<\/strong><\/span><\/h4>\n
              \n
            • sudo \/etc\/init.d\/dnsmasq restart<\/li>\n<\/ul>\n

              \"How<\/p>\n

              Flush BIND DNS Cache<\/strong><\/span><\/h4>\n

              If you\u2019re using BIND, you can clear DNS cache by using one of the following commands:<\/p>\n

                \n
              • sudo \/etc\/init.d\/named restart<\/li>\n<\/ul>\n

                \"How<\/p>\n[ad type=”banner”]\n

                  \n
                • sudo rndc restart<\/li>\n<\/ul>\n

                  \"How<\/p>\n

                    \n
                  • sudo rndc restart<\/li>\n<\/ul>\n

                    \"How<\/p>\n

                     <\/p>\n

                    BIND version 9.3.0, and greater, support flushing DNS cache for a particular domain, as well as for the LAN, or the WAN. You can use the following commands to make use of this feature:<\/p>\n

                      \n
                    • To clear DNS cache for a particular domain, use \u201csudo rndc flushname wikitechy.com<\/strong>\u201c<\/li>\n<\/ul>\n

                      \"How<\/p>\n

                        \n
                      • To clear DNS cache for LAN, use \u201csudo rndc flush lan<\/strong>\u201c<\/li>\n<\/ul>\n

                        \"How<\/p>\n

                          \n
                        • To clear DNS cache for WAN, use \u201csudo rndc flush wan<\/strong>\u201c<\/li>\n<\/ul>\n

                          \u00a0\"How<\/h4>\n[ad type=”banner”]\n

                          Bonus: Change DNS Settings in Ubuntu:<\/strong><\/span><\/h4>\n

                          We\u2019ve been looking at flushing the DNS reserve in Ubuntu, be that as it may, there might be situations where you simply need to roll out an improvement to the DNS settings in Ubuntu. If you want to change the DNS settings in Ubuntu, you can do that utilizing the GUI, or by means of the Terminal.<\/p>\n

                          Change DNS Settings using the GUI:<\/p>\n

                          Utilizing the GUI to change DNS settings is less demanding than utilizing the Terminal. However, if you use multiple connections, you should change the DNS setting for every one of them.\u00a0 To change DNS settings using the GUI, just follow the steps below:<\/p>\n

                            \n
                          1. OpenSystem Settings<\/strong>, and click onNetwork.<\/strong><\/li>\n<\/ol>\n

                            \"How<\/p>\n

                            2.Click on the\u00a0arrow next to the name of the network<\/strong>\u00a0you\u2019re connected to.<\/p>\n

                            \"How<\/p>\n

                              \n
                            1. Now, click on\u201cSettings\u201d.<\/strong>\u00a0This will open up the settings for that connection.<\/li>\n<\/ol>\n

                              \"How<\/p>\n

                                \n
                              1. Switch over to the IPv4 tab<\/strong>, and you\u2019ll see an option called \u201cAdditional DNS Servers<\/strong>\u201c. You can enter the DNS servers you want to use in this field. If you want to enter more than one DNS server, just separate them with commas.<\/li>\n<\/ol>\n

                                \"How<\/p>\n

                                Change DNS Settings using the Terminal:<\/strong><\/span><\/h4>\n

                                If you don\u2019t want to use the GUI, and prefer changing DNS settings using the Terminal, you can do this by adding the nameservers to the dnsmasq config record.\u00a0 However, dnsmasq does not come installed by default in Ubuntu systems (dnsmasq-base, does). So, first you\u2019ll have to install dnsmasq by launching a Terminal, and using \u201csudo apt-get install dnsmasq \u201c.<\/p>\n

                                \"How<\/p>\n

                                  \n
                                • Once you have installed dnsmasq. You can edit the config file with \u201csudo nano \/etc\/dnsmasq.conf<\/strong>\u201c.<\/li>\n<\/ul>\n

                                  \"How<\/p>\n

                                    \n
                                  • Here, you can add your DNS servers\u2019 IP addresses where it says \u201cAdd other nameservers here<\/strong>\u201c.<\/li>\n<\/ul>\n

                                    \"How<\/p>\n[ad type=”banner”]\n

                                    Clear DNS Cache in Linux Using These Methods<\/strong><\/span><\/h4>\n

                                    You can use any of these methods to clear DNS cache in a Linux system. Issues with DNS cache can cause problems such as a webpage not loading, nameserver changes not being recognized by your system, and a lot more. Once you flush DNS cache, these problems will most likely go away.<\/p>\n

                                     <\/p>\n","protected":false},"excerpt":{"rendered":"

                                    How to Flush DNS Cache in Linux – PC – If you\u2019re having trouble connecting to a website, or if you just want a DNS change to be seen by your Ubuntu machine.<\/p>\n","protected":false},"author":1,"featured_media":17892,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1699,5739],"tags":[45128,45122,36759,7423,45123,45135,45112,45110,45101,45138,45111,45131,7413,45113,36758,36765,37005,45130,45106,7412,45092,45102,45104,45125,45115,45103,45114,45093,36755,45118,7424,36747,36762,7417,45117,45136,36774,45108,45116,45129,45099,45127,7418,7411,7420,36999,45119,45094,45095,45098,7416,7419,45139,45145,45144,45146,45109,45100,45126,45133,45120,45137,45142,45107,45132,45121,45124,45143,45134,45140,45105,45096,45097,45141],"class_list":["post-15026","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-linux","category-pc","tag-bind-dns","tag-clear-dns","tag-clear-dns-cache","tag-clear-dns-cache-linux","tag-clear-dns-cache-mac","tag-command-to-flush-dns","tag-configure-dns","tag-configure-dns-server","tag-configure-dns-server-linux","tag-debian-flush-dns","tag-dns-cache","tag-dns-cache-flush","tag-dns-cache-linux","tag-dns-configuration","tag-dns-flush","tag-dns-flush-command","tag-dns-flush-linux","tag-dns-flush-mac","tag-dns-in-linux","tag-dns-linux","tag-dns-resolver-linux","tag-dns-server","tag-dns-server-configuration","tag-dns-server-linux","tag-dns-server-setup","tag-dns-settings","tag-dns-setup","tag-find-dns-server-linux","tag-flush-dns","tag-flush-dns-cache","tag-flush-dns-cache-linux","tag-flush-dns-cache-mac","tag-flush-dns-command","tag-flush-dns-linux","tag-flush-dns-mac","tag-flush-dns-osx","tag-flush-windows","tag-how-to-clear-dns-cache","tag-how-to-flush-dns-cache-in-linux","tag-ipconfig-dns-flush","tag-ipconfig-dnsflush","tag-ipconfig-flushdns","tag-linux-clear-dns-cache","tag-linux-dns","tag-linux-dns-cache","tag-linux-dns-flush","tag-linux-dns-server","tag-linux-dns-server-config","tag-linux-dns-settings","tag-linux-domain-server","tag-linux-flush-dns","tag-linux-flush-dns-cache","tag-linux-refresh-dns","tag-linux-set-dns","tag-linux-set-dns-server","tag-local-dns","tag-local-dns-server","tag-local-dns-server-linux","tag-mac-clear-dns-cache","tag-mac-dns-flush","tag-mac-flush-dns","tag-mac-flush-dns-cache","tag-mac-os-x-flush-dns","tag-make-dns-server","tag-osx-clear-dns-cache","tag-osx-flush-dns","tag-refresh-dns","tag-refresh-dns-cache","tag-reset-dns","tag-reset-dns-cache","tag-service-used-to-start-dns-server","tag-setup-dns-server","tag-setup-dns-server-linux","tag-windows-flush-dns"],"_links":{"self":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts\/15026","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/comments?post=15026"}],"version-history":[{"count":0,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/posts\/15026\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/media\/17892"}],"wp:attachment":[{"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/media?parent=15026"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/categories?post=15026"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wikitechy.com\/technology\/wp-json\/wp\/v2\/tags?post=15026"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}