CINXE.COM
Domain Name System
<!DOCTYPE html> <html lang="en" itemscope itemtype="http://schema.org/WebPage" prefix="og: http://ogp.me/ns#" > <head> <title>Domain Name System</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8" /> <meta property="og:type" content="website" /> <meta name="theme-color" content="#63bb9d"> <script> var dfp_nsfw='N'; </script> <meta property="fb:app_id" content="521724824578638" /> <link href="https://plus.google.com/+robtex" rel="publisher" /> <script> var addthis_config = { data_track_clickback: false } </script> <link rel="search" type="application/opensearchdescription+xml" title="robtex search" href="/osd.xml" /> <link rel="icon" href="https://www.robtex.com/favicon.ico" type="image/x-icon" /> <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1"/> <base href="https://www.robtex.com/dns-lookup/" /><link rel="canonical" href="https://www.robtex.com/en/dns-lookup/"/> <link rel="apple-touch-icon" href="https://www.robtex.com/apple-touch-icon.png" /> <meta itemprop="image" property="og:image" content="https://gfx.robtex.com/gfx/graph.png?dns=&square=256" /> <meta name="twitter:card" content="summary" /> <meta name="twitter:site" content="@robtexdotcom" /> <meta name="twitter:title" content="Domain Name System" /> <meta name="twitter:description" content="" /> <meta name="twitter:image" content="https://gfx.robtex.com/gfx/graph.png?dns=&square=256" /> <meta content="" itemprop="description" name="description" property="og:description"/> <script type="application/ld+json"> { "@context":"http://schema.org", "@type":"NewsArticle", "headline":"", "datePublished":"2017-07-22T12:19:11Z", "author":["Robtex"], "image":{"@type":"ImageObject","url":"https://gfx.robtex.com/gfx/graph.png?dns=&square=1024","height":1024,"width":1024}, "description":"", "publisher":{"@type":"Organization","name":"Robtex", "logo":{"@type":"ImageObject","url":"https://www.robtex.com/robtex.gif","width":190,"height":43} }, "url":"https://www.robtex.com/dns-lookup/" } </script> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-9079685345082025" crossorigin="anonymous"></script> <script> var isq=1; var ise=0; var rtrk=1500725951; var isaj=0; var rtpv=0; var acceptedcookies=0; var baseurl='https://www.robtex.com/'; var protohost='https://www.robtex.com'; var shbbu='"?dns="'; var yesads=1; var promoext=0; var didpromo=0; window.addEventListener( "pageshow", function ( event ) { var historyTraversal = event.persisted || ( typeof window.performance != "undefined" && window.performance.navigation.type === 2 ); if ( historyTraversal ) { // Handle page restore. window.location.reload(); } }); function dopromoext() { return; if(!promoext) return; var x=document.getElementById("promoext"); if(x) { if(didpromo++) return; x.innerHTML="<div style=\"background:#eee;padding:10px;margin:10px auto;border-radius:15px;width:300px\"><center><a href=\"https://www.robtex.com/toolbar/\">Try our chrome extension!</a></center></div>"; } } function trypromo() { if(!acceptedcookies) return; if(window['chrome']) if(window['chrome']['runtime']) chrome.runtime.sendMessage( 'neagmbhdnabclgpgjkpepoahjkafipbn' , { message: "version" }, function (reply) { if (reply) { } else { promoext = 1; dopromoext(); } }); } function getcookie(n) { var name=n+"="; var found=undefined; var ca = document.cookie.split(';'); for(var i = 0; i <ca.length; i++) { var c = ca[i]; while (c.charAt(0)==' ') { c = c.substring(1); } if (c.indexOf(name) == 0) { found=c.substring(name.length,c.length); } } return found; } function setcookie(o) { var exdays=o.d; var d = new Date(); d.setTime(d.getTime() + (exdays*24*60*60*1000)); var expires = "expires="+ d.toUTCString(); document.cookie = o.n+"="+o.v + ";" + expires + ";path=/"; } function acceptcookies(a) { acceptedcookies=a; setcookie({'n':'acceptcookies','v':a,'d':30}); checkcookies(); return false; } function checkcookies() { let q=document.getElementById('cookienotice'); if(q) q.style.display=(acceptedcookies==1?'none':'block'); } function dortpv() { rtpv=getcookie('rtpv')||0; rtpv++; // console.log('rtpv',rtpv); setcookie({'n':'rtpv','v':rtpv,'d':365}); } acceptedcookies=!!getcookie('acceptcookies'); dortpv(); </script> <style>a { color: #000; } * { box-sizing: border-box; } table.dnsh { background: #eee; } td.dnsht { background: #0c0; } td.dnshf { background: #ccc; } html,body { margin: 0px; padding: 0px; width: 100%; background: #fff; } .rtad { visibility: hidden; } body { font-family: "Trebuchet MS", Arial, Helvetica, sans-serif; font-size: 18pt; line-height: 1.5; text-rendering: optimizeLegibility; width: 100%; } #contres { } #mynetwork { height: 100%; } #mynetworkflex { display: flex; width: 100%; height: 100%; } #mynetworkcanvas { height: 100%; flex-grow: 1; flex: 1; } .rtfrag { } .rtfragmax { height: 100%; } .rtgui { display: flex; flex-direction: column; flex-wrap: wrap; } .rtfragui { border: 3px solid #63bb9d; width: 100%; margin: 1em 0; } .rtfragh { background: #63bb9d; margin: none; padding: 1px; display: flex; flex-direction: row; } .rtfragh > div { } .rtfragh > div:nth-child(1) { flex: 1; } .rtfragh > div:nth-child(2) { } .rtfragh > div:nth-child(2) > span > a { border-bottom: none; } .rtfragh > div > div { } .rtfragh> div > h2 { background: #63bb9d; padding: none; margin: none; border: none; margin: 0 0.1em; } .rtfragc { overflow: scroll; } .rtfullheight { } .rtstyle table { border-radius: 10px 0 0 10px; } .rtstyle table table { } .rtstyle td, .rtstyle th { } .whois td { vertical-align: top; } .whois td:first-child { color: #008; text-align: right; padding-right: 10px; width: 100px; } .thmitable td { vertical-align: top; max-width: 250px; overflow: scroll; } .thmitable td:first-child { color: #008; text-align: right; padding-right: 10px; width: 150px; } table.thmitable { border-radius: 0 0 0 0; border: 1px solid #ccc; width: 100%; padding: 10px 0; margin: 10px 0; } table.whois { border-radius: 0 0 0 0; border: 1px solid #ccc; width: 100%; padding: 10px 0; margin: 10px 0; } .rtpopup table { width: 100%; border: 1px solid black; border-radius: 0; } div.res > div { width: 100%; overflow: hidden; } #res table { } #res table td td { } #res table td td td { } #res table td { } #res table th { } #res table td { } div.cards > div { background: #c6d0c6; border: 1px solid #585; border-radius: 15px; padding: 10px; } div.cards > div >h2 { border-radius: 10px; background: #fff; border: 1px solid #585; margin: 10px; padding: 10px; } div.cards >div>h2>span { padding-top: 50px; } sup { font-weight: bold; } div.index { background: #c6d0c6; margin: 30px 0; border-radius: 15px; padding: 10px; width: 100%; } div.index > div { border-radius: 5px; background: #fff; border: 1px solid #585; overflow-y: scroll; margin: 10px; height: 150px; } span.resspan { } div.contad { } div.dns table { width: 100%; text-align: left; vertical-align: top; margin: 0; } div.dns td, div.dns th { vertical-align: top; } div.dns th { font-weight: normal; text-align: r; } div.dns td > b { color: rgba(0,0,0,.5); text-align: right; float: right; } div.dns table > tbody > tr >td:nth-child(2) { width: 100%; } table.l2 ,table.l4 ,table.l6 ,table.l8 { margin: 0.5em 0; } table.l0 { background: #eee; } table.l0 table.l2:nth-child(even), table.l4 table.l6:nth-child(even) { background: #eef; } table.l0 table.l2:nth-child(odd), table.l4 table.l6:nth-child(odd) { background: #efe; } table.l2 table.l4:nth-child(even), table.l6 table.l8:nth-child(even) { background: #fee; } table.l2 table.l4:nth-child(odd), table.l6 table.l8:nth-child(odd) { background: #ffe; } .rtsak { margin: 0; padding: 0; position: absolute; top: 0; left: 0; width: 100%; overflow: hidden; } #dbg { font-family: monospace; color: white; background: black; float: right; } div.rtstyle a { text-decoration: underline; text-decoration-color: #ccc; white-space: nowrap; } div.brk { clear: both; height: 3px; background: #ccc; margin: 5px; border-radius: 3px; background: linear-gradient(90deg, #fff 00px,#ccc 25%,#ccc 75%,#fff 100%); } #prog { } #prog , #prog div { font-family: Courier; height: 3px; position: fixed; width: 100%; max-width: 100%; overflow: hidden; margin: 0; padding: 0; top: 0; left: 0; z-index: 1000; } #prog div { } #prog div div:nth-child(1) { background: rgba(0,0,255,0.4); } #prog div div:nth-child(2) { background: rgba(255,0,0,0.4); } #prog div div:nth-child(3) { background: rgba(128,128,128,0.4); } #prog div div:nth-child(4) { color: #fff; } div.dnsbl { width: 100%; max-width: 100%; overflow: hidden; } div.dnsbl table, div.dnsbl tr, div.dnsbl td { } div.dnsbl table { width: 100%; max-width: 100%; overflow: hidden; } div.dnsbl tr { } div.dnsbl td { overflow-wrap: break-word; } div.dnsbl table tr td:first-child { } div.dnsbl tt { float: left; margin: 0px 10px; border: 1px solid black; background: #fff; color: #000; } div.dnsbl i { clear: both; float: left; } div.dnsbl table tr:not(:last-child) td { border-bottom: 2px rgba(0,0,0,.5) dashed; } div.dnsbl tr { background: #eee; padding: 0.2em 0px; } div.dnsbl tr.red { background: #fdd; color: #c00; } div.dnsbl tr.error { background: #ffc; color: #000; } div.dnsbl tr.ok { background: #dfd; } div.autofold { padding: 3px; width: 100%; display: flex; overflow: wrap; border: 3px solid #000; } .autofold div { overflow: wrap; display: flex; border: 1px solid #0f0; } div.autofold2 { clear: both; flex-flow: row wrap; width: 100%; display: flex; qborder: 3px solid #000; } .autofold2 div { flex: 1; background: #fff; display: flex; jborder: 1px solid #800; } .autofold2 div { padding: 1px; border: 1px solid #000; border-radius: 5px } prog#div { z-order: 1000; } .scrollist > li { list-style: none; max-width: 200px; min-width: 100px; white-space: nowrap; } .scrollist { } .scrollist::-webkit-scrollbar { -webkit-appearance: none; height: 10px; } .scrollist::-webkit-scrollbar-thumb { background-color: rgba(0,0,0,.5); } .scrollist::-webkit-scrollbar { background-color: rgb(99, 187, 157); border: none; } .rtstyle h2, .rtstyle h3 { text-align: center; background: #eee; border-bottom: 1px solid #ccc; } @media screen and (max-width: 499px) { #mynetworkdragl, #mynetworkdragr { width: 30px; background: url( data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAAICAYAAAA4GpVBAAAAGUlEQVQYV2O4e/fuf4bdu3cjEzNnzkQXAwADDhmBxLFwEwAAAABJRU5ErkJggg== ) repeat; } .scrollist { columns: 200px; overflow-x: auto; max-height: 100px; } } .notfound:after { display:block; content:'Nothing found here, sorry'; color:#008 } .pleaselogin:after { display:block; content:'Please login to see this section'; color:#008; } .loading:after { display:block; content:'loading...'; color:#008; } @media screen and (min-width: 500px) { body { font-size:11pt; } .rtstyle { } .scrollist { clear: none; font-family: verdana,arial,sans-serif; max-width: 100%; overflow-x: hidden; padding: 2px; overflow-y: auto; max-height: 600px; margin: 0; border-bottom: 2px solid #ccc; border-top: 2px solid #ccc; } .rtstyle h2, .rtstyle h3 { text-align: left; padding-left: 20px; } .infobox { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: flex-start; } .infobox > div { border: #63bb9d solid 1px; margin: 5px; flex-grow: 1; flex-shrink: 1; box-shadow: 7px 7px 10px 0px #ddd; border-radius: 4px; } } .infobox h3 { border: 0; margin: 0; background: #63bb9d; } .img24 { width: 24px; height: 24px; } .img_restore { background-image: url("data:image/svg+xml,%3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3Cpath d='M5 16h3v3h2v-5H5v2zm3-8H5v2h5V5H8v3zm6 11h2v-3h3v-2h-5v5zm2-11V5h-2v5h5V8h-3z'/%3E %3C/svg%3E"); } .img_fullscreen { background-image: url("data:image/svg+xml, %3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3Cpath d='M7 14H5v5h5v-2H7v-3zm-2-4h2V7h3V5H5v5zm12 7h-3v2h5v-5h-2v3zM14 5v2h3v3h2V5h-5z'/%3E %3C/svg%3E"); } .img_bottom { background-image: url("data:image/svg+xml, %3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M16 13h-3V3h-2v10H8l4 4 4-4zM4 19v2h16v-2H4z'/%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3C/svg%3E"); } .im_top { background-image: url("data:image/svg+xml, %3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M8 11h3v10h2V11h3l-4-4-4 4zM4 3v2h16V3H4z'/%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3C/svg%3E"); } .rtpopup table td { border: 1px; } .rtpopup table td a { text-decoration: none; } .rtpopup table td strike { color: #f00; } .rtpopup table td b { text-decoration: none; } .ttal , .rtpopup table td.shared1 { text-align: left; background: linear-gradient(30deg, #ccf 10%,#fff 90%); } .ttar, .rtpopup table td.shared2 { text-align: right; background: linear-gradient(30deg, #fff 10%,#cfc 90%); } .rtpopup table td.shared3 { text-align: center; background: linear-gradient(90deg, #ccc 10%,#ccc 90%); } .rtpopup table tr.l0 { background: #fcc; } .rtpopup table tr.l1 { background: #eec; } .rtpopup { min-width: 100px; min-height: 100px; background: #fff; box-shadow: 10px 10px 10px 0 rgba(0,0,0,0.1); border-radius: 5px; border: 4px solid #ccc; padding: 4px; max-height: 500px; overflow: scroll; z-index: 1111; } .rtpopup::-webkit-scrollbar { -webkit-appearance: none; height: 10px; } .rtpopup::-webkit-scrollbar-thumb { background-color: rgba(0,0,0,.5); } .rtpopup h1 { margin: 0px; font-size: 14px; } .flex1 { display: flex; flex-wrap: wrap; } .flex1 > div { flex: 1; } .seo table { border: 1px solid black; min-width: 300px; border-radius: 3px; margin: 3px; } .endsection { font-style: italic; font-weight: lighter; clear: both; text-align: right; } .xsha { display: flex; flex-wrap: wrap; } .xsha > div { page-break-inside: avoid; -webkit-column-break-inside: avoid; padding: 5px 10px 10px 5px; } .xsha>div>div { background: #63bb9d; color: #1f701f; min-height: 50px; } .xsha > div > div > span { padding: 10px; } .xsha h3 { color: #ffffff; margin: 0px; padding: 7px; background: #63bb9d; border: none; } .xbul { border: 1px solid #000000; clear: none; font-family: verdana,arial,sans-serif; max-height: 300px; margin: 0; overflow-x: auto; padding: 2px; max-width: 100%; padding: 9px; } .xbul li { list-style-type: none; margin-left: 0px; display: list-item; } .xsha>div { page-break-inside: avoid; -webkit-column-break-inside: avoid; padding: 5px 10px 10px 5px; } .old h3 { background: none; border: none; } @media (max-width: 767px) { .xbul { max-height: 140px; columns: 300px; } } @media (max-width: 767px) { .xsha>div { width: 100%; } } @media (min-width: 768px) { .xsha>div { width: 300px; } } .anchor { content: 'ANCHOR'; position: relative; top: -100px; display: inline; } div.rttab ul { display: flex; flex-wrap: wrap; } div.rttab button, div.rttab li { color: #1f701f; font-family: arial; padding: 3px; flex: 1; word-break: normal; margin: 2px; text-align: center; border: 2px solid #1f701f; border-radius: 3px; background: #fff; color: #000; text-decoration: none; font-size: 10px; } div.rttab a { text-decoration: none; } div.rttab ul { list-style-type: none; margin: 0; padding: 0; } div.rttab li { } span.censor { background: #888; } span.censor:hover { background: none; } span.censor:hover:before { background: #f0f; content: attr(data-hover); position: absolute; overflow: visible; z-index: 2000; } span.censor:hover:before { background: #ff0; } table.protable { border-radius: 0; border-collapse: collapse; width: 100%; } table.protable tr { } table.protable td { padding: 10px; } table.protable tr:nth-child(even) td { background: #eef; } table.protable tr:nth-child(odd) td { background: #efe; } table.protable th { background: #ccc; } table.table2col { border-radius: 0; width: 500px; border: 1px solid #ccc; border-collapse:collapse; margin:0 30px; } table.table2col tr { width: 400px; } table.table2col td , table.table2col th { padding:4px 7px; } table.table2col tr.ttog0 td { background: #eef; } table.table2col tr.ttog0 th { background: #ccf; } table.table2col tr.ttog1 td { background: #efe; } table.table2col tr.ttog1 th[scope=row] { background: #cfc; } table.table2col th:not([scope=row]) { background:#ccc; } table.table2col th[scope=row] { vertical-align: top; text-align:left; width:140px; } table.table2col td { background:#f0f; } table.table2col ul { padding:0; margin:0; } table.table2col li { list-style: none; white-space: nowrap; } .button { background: #f8f8f8; border-radius: 3px; padding: 3px; } div.loginbar { background: #ccc; font-size: 10px; display: flex; justify-content: flex-end; } div.loginbar > div { flex: 1; flex-grow: 0; white-space: nowrap; } div.loginbar .button { border: none; cursor: pointer; margin: 0 5px; } div.loginbar .button a { text-decoration: none; } .img24 { width: 24px; height: 24px; display: inline-block; border: none; background: none; } .img_restore { background-image: url("data:image/svg+xml,%3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3Cpath d='M5 16h3v3h2v-5H5v2zm3-8H5v2h5V5H8v3zm6 11h2v-3h3v-2h-5v5zm2-11V5h-2v5h5V8h-3z'/%3E %3C/svg%3E"); } .img_fullscreen { background-image: url("data:image/svg+xml, %3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3Cpath d='M7 14H5v5h5v-2H7v-3zm-2-4h2V7h3V5H5v5zm12 7h-3v2h5v-5h-2v3zM14 5v2h3v3h2V5h-5z'/%3E %3C/svg%3E"); } .img_bottom { background-image: url("data:image/svg+xml, %3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M16 13h-3V3h-2v10H8l4 4 4-4zM4 19v2h16v-2H4z'/%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3C/svg%3E"); } .img_top { background-image: url("data:image/svg+xml, %3Csvg fill='%23000000' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'%3E %3Cpath d='M8 11h3v10h2V11h3l-4-4-4 4zM4 3v2h16V3H4z'/%3E %3Cpath d='M0 0h24v24H0z' fill='none'/%3E %3C/svg%3E"); } #rtfragc_visgraph { height: 500px; } #rtfragc_dnst, #rtfragc_dnsbl, #rtfragc_ohistory, #rtfragc_owhois { height: 300px; } #rtfragc_ograph { overflow: scroll; } @keyframes spin { to { transform: rotate(1turn); } } .aspan { display: inline; background: #f0f; } .dlicon { display: inline-block; width: 20px; clear: none; } .progress { position: relative; display: inline-block; width: 5em; height: 5em; margin: 0 .5em; font-size: 12px; text-indent: 999em; overflow: hidden; animation: spin 1s infinite steps(8); } .small.progress { font-size: 4px; } .large.progress { font-size: 24px; } .progress:before, .progress:after, .progress > div:before, .progress > div:after { content: ''; position: absolute; top: 0; left: 2.25em; width: .5em; height: 1.5em; border-radius: .2em; background: #eee; box-shadow: 0 3.5em #eee; transform-origin: 50% 2.5em; } .progress:before { background: #555; } .progress:after { transform: rotate(-45deg); background: #777; } .progress > div:before { transform: rotate(-90deg); background: #999; } .progress > div:after { transform: rotate(-135deg); background: #bbb; } .dlicon>a { border-bottom: none ; } header, footer { overflow-x: hidden; } .adc { margin: 0 auto; padding: 0 0 0 0; /*border:1px solid #00f; */ } div.marg { display:flex } div.marg > div { /*flex:1;*/ overflow:hidden; } div.marg > div:nth-child(2) { flex:1; } div.marg > div:nth-child(1) , div.marg > div:nth-child(3) { /*background: #ccc; min-width:30px;*/ } @media (max-width: 767px) { div.marg > div:nth-child(1) , div.marg > div:nth-child(3) { display:none; } } div.inputform { display: flex; } div.inputtext { flex-grow: 1; } input#q {width:100%;height:30px;margin: 10px 0;} input#q, input#go { width: 100%; height: 30px; margin: 10px 0px; border: 1px solid #63bb9d; } h1#supertitle > a { text-decoration-line: underline; text-decoration-color: #1f701f; color: #1f701f; } .titlecrumb { display:flex; flex-direction:row; } div.rttab li { min-width: 100px; } #supertitle { text-align: center; border: 0; background: #63bb9d; color: #1f701f; margin: 0; text-overflow: ellipsis; white-space: nowrap; overflow: hidden; font-size: 2.2em; } #supercrumb a, #supernav a { color: #ffffff; text-decoration: none; } #supercrumb>span+span:before { color: #1f701f; content: '>>>'; } #supertop { background: #63bb9d; min-height: 50px; } #supertop { border: 0; margin: 0 0 1em 0; box-shadow: 0 0.3em 1em 0.1em #ccc; padding: 1em; } #supercrumb { display: block; border: 0; padding: 0.5em; color: #ffffff; margin: 0; text-overflow: ellipsis; overflow: hidden; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; direction: rtl; text-align: right; } footer { background: #63bb9d; color: #1f701f; } footer li { list-style: none; } footer ul { display:flex; 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color: #000; transition: all .4s ease-in-out; } */ div.cookieclass { background: rgba(255,255,255,0.9); border-top: 2px solid #ddd; color: #000; font-size: 40px; position: fixed; overflow: hidden; box-sizing: border-box; font-family: Helvetica,Calibri,Arial,sans-serif; font-size: 16px; line-height: 1.5em; display: -ms-flexbox; display: flex; -ms-flex-wrap: nowrap; flex-wrap: nowrap; z-index: 9999; left: 0; right: 0; bottom: 0; align-items: center; min-height: 80px; } div.cookieclass > div{ margin: 10px; } div.cookieclass > div:nth-child(1){ flex: 1; } div.cookieclass > div:nth-child(2){ } div.cookieclass a,div.cookieclass a:visited { color:$fgforwhite2; } div.cookieclass > div:nth-child(2) a{ background: #000; color:#fff; padding: 8px; border-radius: 10px; text-decoration: none; } div.preview { position:relative; overflow:hidden; width:700px; /* border:1px solid #000; */ } div.preview > table { border:2px solid #ccc; border-collapse: collapse; } div.preview > table th, div.preview > table td { border:2px solid #ccc; } div.preview > table td { min-width:120px; max-width:120px; overflow:hidden; text-overflow: ellipsis; white-space: nowrap; } div.preview > table th, div.preview > table tr > td:first-child { font-weight: bold; background:#eee; min-width:20px; text-align:center; } div.fadeendv { display: block; position: absolute; height: 100px; width: 100%; background: linear-gradient(rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 1) 100%); bottom: 0; } div.fadeendh { display: block; position: absolute; height: 100%; width: 100px; background: linear-gradient(90deg,rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 1) 100%); right: 0; top:0; } a.download { background: #008800; position: relative; padding: 7px 12px; height: 30px; line-height: 30px; border: 3px solid #12ff75 ; font-size: 24px; color: #fff; font-weight: bold; font-family: "Helvetica Neue",Helvetica,Arial,sans-serif; text-shadow: 0 -1px 0 rgba(0,0,0,0.25); box-shadow: inset 0 1px 0 rgba(255,255,255,0.25); border-radius: 4px; } /* Dropdown Button */ .dropbtn { /* background-color: #4CAF50; */ /* color: white; padding: 16px; font-size: 16px;*/ border: none; cursor: pointer; } /* The container <div> - needed to position the dropdown content */ .dropdown { position: relative; display: inline-block; } /* Dropdown Content (Hidden by Default) */ .dropdown-content { display: none; position: absolute; background-color: #f9f9f9; min-width: 160px; box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2); z-index: 1; } /* Links inside the dropdown */ .dropdown-content a { color: black; padding: 0px 6px; text-decoration: none; display: block; } /* Change color of dropdown links on hover */ .dropdown-content a:hover {background-color: #f1f1f1} /* Show the dropdown menu on hover */ .dropdown:hover .dropdown-content { display: block; } /* Change the background color of the dropdown button when the dropdown content is shown */ .dropdown:hover .dropbtn { background-color: #ecefe0; }</style> <script async src="https://www.googletagmanager.com/gtag/js?id=G-BE750HJ7QP"></script> <script> window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('js', new Date()); gtag('config', 'G-BE750HJ7QP'); </script> </head> <body style=" margin: 0 auto; max-width: 1000px;" > <div id="sse0"></div> <div id="sse1"></div> <span class="classhash" id="dns="></span> <span class="classhashbang" id="!dns="></span> <div id="zz" style="display:none"> <div class="zzzbase" id="zzz01"> </div> <div class="zzzbase" id="zzz02"> </div> <div class="zzzbase" id="zzz03"> </div> <div class="zzzbase" id="zzz04"> </div> <div class="zzzbase" id="zzz05"> </div> <div class="zzzbase" id="zzz06"> </div> <div class="zzzbase" id="zzz07"> </div> <div class="zzzbase" id="zzz08"> </div> </div> <header> <div class='loginbar'><div><span class="button"><a href="/dashboard/">Login</a></span></div> </div> <div id="supertop"> <div class="titlecrumb"> <div><h1 id="supertitle">Domain Name System</h1> </div> <div id="supernav"> </div> <div id="supercrumb" style="flex:1"> <br/> </div> </div> </div> <div style="margin: 0 auto;height:250px;max-width: 970px;"> <ins class="adsbygoogle" style="display:inline-block;width:100%;height:250px" data-ad-client="ca-pub-9079685345082025" data-ad-slot="4999918576"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> </header> <main> <article id="superarticle"> <div id="supercontainer"> <div id="zzztopad" class="notinapp onew"> </div> <br/> <div itemscope itemtype="http://schema.org/WebSite"> <meta itemprop="url" content="https://www.robtex.com/"/> <script> function onsub(x) { var v=document.forms['f1'].q.value; var nurl="https://www.robtex.com/search/?q="+v; document.location=nurl; return false; } function onchg() { return false; } </script> <form id="f1" onsubmit="return onsub('')" action="https://www.robtex.com/search/" itemprop="potentialAction" itemscope itemtype="http://schema.org/SearchAction"> <meta itemprop="target" content="https://www.robtex.com/search/?q={q}"/> <div class='inputform' > <div class='inputtext' ><input id="q" oninput="return onchg();" onpropertychange="return onchg();" class="zinputtext" autocorrect="off" autocapitalize="off" spellcheck="false" placeholder="hostname, ipnumber, route or AS-number" title="domain name, ip number, as number, route" itemprop="query-input" type="text" name="q" value="" required /> </div> <div class='inputsubmit'> <input id='go' name='go' type=submit value='GO' /> </div> </div> </form> </div> <div class='zenter'> <div> </div> <div> </div> <span id="promoext"></span> <script> trypromo(); </script> </div> <div id="superdiv"> <p class="c0"><span>When packet switching networks were first developed, addressing was exclusively numerical. With networks such as The Advanced Research Projects Agency Network (ARPANET), there was little need for developing alternative methods as the number of participating nodes were limited. However, as the network expanded, it soon became evident that while using numerics was a very methodical approach, the addresses themselves proved increasingly hard for humans to memorize. The first solution was to distribute a file called ‘hosts.txt’ to all the nodes of the network, allowing them to map names to the addresses. However, keeping such a centralized system up-to-date would prove difficult. It was clear that a more scalable and automated solution was needed. In 1982, the original system was replaced by the Domain Name System (DNS), which is a hierarchical distribution system that allows IP-addresses and domain names to be assigned to each other in both directions. This enables people to access ‘example.com’, instead of its IP-address ‘192.0.43.10’.</span></p> <p class="c5 c0"></p> <p class="c0"><span>A domain name can be separated into different entities, or</span> <span class="c2">labels</span><span>, consisting of the top-level domain (</span><span class= "c4">.com</span><span>) and at least one sub domain (</span><span class="c4">example</span><span>.com). In addition, there can be up to 127 levels of sub domains (</span><span class= "c4">something</span><span>.example.com and</span> <span class= "c4">something.something</span><span>.example.com). To keep track of this, DNS-servers are assigned different zones containing domains of responsibility. This allows for the system to be balanced and decentralized. At the very top are thirteen root servers, listing the authoritative name servers for the top-level domains that make up the second level.</span></p> <p class="c5 c0"></p> <p class="c0"><span>When you connect to a service running at www.example.com, a query is sent using a resolver. The first recipients of the full query are the root servers that quickly reply by listing the authoritative name servers (in this case c.gtld-servers.net) responsible for ‘.com’. This is done because the root servers have no information on the IP of the full query. A new query is then initiated for each level, where the target is defined by the previous level, following the path downwards until the query matches the initial one. The response contains the IP-address (the A/AAAA-record) for the domain name. To make this less resource exhausting, cache servers are used to store results for a configured period of time, so that you do not have to query the root servers every time you want to perform a nslookup. Below is an example of a non-cached query:</span></p> <p class="c5 c0"></p> <table> <thead><tr><th colspan="2">Me</th><th>Query/Reply</th><th colspan="2">Nameserver </th></tr> </thead> <tbody> <tr><td> Visit www.example.com</td><td>→</td><td>IP of www.example.com?</td><td>→</td><td>a.root-servers.net </td></tr><tr><td> Me</td><td>←</td><td>No info on full IP. Ask m.gtld-servers.net about .com</td><td>←</td><td>a.root-servers.net </td></tr><tr><td> Me</td><td>→</td><td>IP of www.example.com?</td><td>→</td><td>m.gtld-servers.net </td></tr><tr><td> Me</td><td>←</td><td>No info on full IP. Ask b.iana-servers.net about example.com</td><td>←</td><td>m.gtld-servers.net </td></tr><tr><td> Me</td><td>→</td><td>IP of www.example.com?</td><td>→</td><td>b.iana-servers.net </td></tr><tr><td> Me</td><td>←</td><td>www.example.com has IP 192.0.43.10</td><td>←</td><td>b.iana-servers.net </td></tr> </tbody> </table> <p class="c5 c0"></p> <p class="c0"><span>By entering a domain name in the field above, you will get detailed information on the nameservers associated with a domain name.</span></p> <br/></div> <div style="clear:both"></div> </div> </article> <div id='zsocial'> </div> </main> <div class="soctop"> <div id="divaddthis" class="addthis_inline_share_toolbox"></div> <div><a class="twitter-follow-button" href="https://twitter.com/robtexdotcom" data-show-screen-name="false" data-show-count="true" data-size="large"> Follow</a></div> </div> <footer> <ul> <li> <div>Robtex</div> <ul> <li><a class="rtgo" href="https://twitter.com/robtexdotcom">Twitter</a></li> <li><a class="rtgo" href="https://www.facebook.com/robtexdotcom">Facebook</a></li> <li><a class="rtgo" href="https://plus.google.com/+robtex">Google+</a></li> <li><a class="rtgo" href="https://www.linkedin.com/company/robtex">LinkedIn</a></li> </ul> </li> <li> <div>About</div> <ul> <li><a href="/">Home</a></li> <li><a href="/privacy-policy">Privacy Policy</a></li> <li><a href="/api/">API</a></li> <li><a href="/stats/">Statistics</a></li> </ul> </li> <li> <div>Sections</div> <ul> <li><a href="/dns-lookup/">DNS</a></li> <li><a href="/ip-lookup/">IP</a></li> <li><a href="/as/">AS Numbers</a></li> <li><a href="/asmacro/">AS Macros</a></li> <li><a href="/cidr/">Network Routes</a></li> <li><a href="/premium/">Premium Reports</a></li> </ul> </li> </ul> © 2020 Robtex <hr/> <span id="statusgif"></span> <script> //loadflags|=2; //doit(); </script> <div style=""></div> </footer> <div id="sse2"></div> <script> checkcookies(); </script> This site is protected by reCAPTCHA and the Google <a href="https://policies.google.com/privacy">Privacy Policy</a> and <a href="https://policies.google.com/terms">Terms of Service</a> apply. <style> .grecaptcha-badge { display: none; } </style> <script type="text/javascript"> var onloadCallback = function() { grecaptcha.ready(function() { grecaptcha.execute('6LcNupIUAAAAAKqpkrqfj8RXxPKYuJJ7QNnfUzoA', {action: 'hit'}) .then(function(token) { var elem = document.createElement('script'); elem.src = '/rtx/recaptcha/'+token; elem.async = true; elem.type = "text/javascript"; document.head.appendChild(elem); console.log(token); }); }); }; </script> <script src="https://www.google.com/recaptcha/api.js?onload=onloadCallback&render=6LcNupIUAAAAAKqpkrqfj8RXxPKYuJJ7QNnfUzoA" async></script> </body> </html>