After updating the zone file Free sex chatlines local

Understanding DNS and its working is one of the most difficult computer engineering subject and yet most experienced network administrators struggle in this topic when it comes to DNS zone file writing. (see RFC 1912 section 2.3) In the above example we are mapping each NS records to IP address (A record) thus binding nameservers to IP (that is glue them).

Before I proceed with this article, the following are the MOST IMPORTANT points you should remember as otherwise you wouldnt understand bit. An A Record must ALWAYS contain IP address (map host to IP) Whenever you specify A record it must contain IP address on the Right side. A nameserver which gives non-authoritative answer is usually called 'LAME'. An example of lame delegation is ns1.is configured to have zone information about domain but ns2.was not configured properly and does not have any information about the domain.

Placing CNAME along with NS the all of namservers will fail and will result in lame delegation. Although it is very common practice to run both nameservers on same server or subnet, it would not provide fault tolerance.

If the server fails your nameservers will fail and your site wont load.

For proper mail delivery, the following anti-spam methos are very important to make sure the email is delivered to users inbox.dig @ns1.dig @ns2.Since there is no ANSWER section or IP address both the nameservers does not constitute open dns server.If you happen to run bind8 or later, all you have to do is set 'recursion no' within options to disable dns server answering recursive queries.To illustrate this, we have two nameservers running bind for domain We ask ns1.example to resolve outside domain and if we get IP address (A record) in the answer section, then it means it is an 'open dns server'.

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