{"id":2126,"date":"2013-06-27T11:50:33","date_gmt":"2013-06-27T03:50:33","guid":{"rendered":"http:\/\/rmohan.com\/?p=2126"},"modified":"2013-06-27T11:56:13","modified_gmt":"2013-06-27T03:56:13","slug":"configure-caching-name-server-on-centos-6","status":"publish","type":"post","link":"https:\/\/mohan.sg\/?p=2126","title":{"rendered":"Configure Caching Name Server on CentOS 6"},"content":{"rendered":"

Configure Caching Name Server on CentOS 6<\/strong><\/p>\n

A caching only DNS server caches DNS query results for the domain name being queried. These chache are stored for pre specified time known as the TTL ( time-to-live )<\/p>\n

Step 1: Install the BIND Packages using Yum<\/p>\n

Install bind packages using below command. In CentOS\/RHEL 6 chaching-nameserver package has been included with bind package.<\/p>\n

# yum install bind bind-chroot
\nStep 2: Copy default bind configuration File<\/p>\n

Copy bind configuration file from bind sample files using below command. Change the path of files as per version you have installed.<\/p>\n

cd \/var\/named\/chroot\/etc
\ncp \/usr\/share\/doc\/bind-9.9.2\/sample\/etc\/named.conf .
\ncp \/usr\/share\/doc\/bind-9.9.2\/sample\/etc\/named.rfc1912.zones .
\nStep 3: Make changes in Configuration File<\/p>\n

Edit bind configuration file in your favorite editor and make necessory changes as per below settings or use below configuration.<\/p>\n

\/\/ \/var\/named\/chroot\/etc\/named.conf
\noptions {
\nlisten-on port 53 { 127.0.0.1; any; };
\nlisten-on-v6 port 53 { ::1; };
\ndirectory “\/var\/named”;
\ndump-file “\/var\/named\/data\/cache_dump.db”;
\nstatistics-file “\/var\/named\/data\/named_stats.txt”;
\nmemstatistics-file “\/var\/named\/data\/named_mem_stats.txt”;
\nallow-query { localhost; any; };
\nallow-query-cache { localhost; any; };
\nrecursion yes;<\/p>\n

dnssec-enable yes;
\ndnssec-validation yes;
\ndnssec-lookaside auto;<\/p>\n

\/* Path to ISC DLV key *\/
\nbindkeys-file “\/etc\/named.iscdlv.key”;<\/p>\n

managed-keys-directory “\/var\/named\/dynamic”;
\n};<\/p>\n

logging {
\nchannel default_debug {
\nfile “data\/named.run”;
\nseverity dynamic;
\n};
\n};<\/p>\n

include “\/etc\/named.rfc1912.zones”;
\nUpdate permissions on configuration files.<\/p>\n

# chown root:named named.conf named.rfc1912.zones
\nStep 4: Check Configuration File<\/p>\n

We recommend to check dns configuration file before restarting service.<\/p>\n

# named-checkconf named.conf
\nStep 5: Restart Bind Service<\/p>\n

Start Bind (named) service using below command.<\/p>\n

# service named restart
\nEnable auto start bind service on system boot.<\/p>\n

# chkconfig named on
\nStep 6: Finally test Caching Only DNS Setup<\/p>\n

Send query to your dns server directly using below command.
\nSyntax: nslookup < domainname > < caching dns server name\/ip ><\/p>\n

# nslookup yahoo.com 192.168.1.10
\nSample Output:<\/p>\n

Server: 192.168.1.11
\nAddress: 192.168.1.11#53<\/p>\n

Non-authoritative answer:
\nName: yahoo.com
\nAddress: 98.138.253.109
\nName: yahoo.com
\nAddress: 98.139.183.24
\nName: yahoo.com
\nAddress: 206.190.36.45
\nIf you want to install Master dns server. Follow below link<\/p>\n","protected":false},"excerpt":{"rendered":"

Configure Caching Name Server on CentOS 6<\/p>\n

A caching only DNS server caches DNS query results for the domain name being queried. These chache are stored for pre specified time known as the TTL ( time-to-live )<\/p>\n

Step 1: Install the BIND Packages using Yum<\/p>\n

Install bind packages using below command. In CentOS\/RHEL 6 chaching-nameserver […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[15],"tags":[],"_links":{"self":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/2126"}],"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=2126"}],"version-history":[{"count":4,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/2126\/revisions"}],"predecessor-version":[{"id":2129,"href":"https:\/\/mohan.sg\/index.php?rest_route=\/wp\/v2\/posts\/2126\/revisions\/2129"}],"wp:attachment":[{"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2126"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2126"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mohan.sg\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2126"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}