{"id":17571,"date":"2020-10-27T20:32:41","date_gmt":"2020-10-27T20:32:41","guid":{"rendered":"http:\/\/dev.profelis.net\/?p=17571"},"modified":"2023-02-01T10:57:59","modified_gmt":"2023-02-01T07:57:59","slug":"dns-nedir","status":"publish","type":"post","link":"https:\/\/profelis.com.tr\/en\/2020\/10\/27\/dns-nedir\/","title":{"rendered":"DNS Nedir?"},"content":{"rendered":"<p dir=\"ltr\"><span style=\"color: #000000;\">DNS Ingilizce \u2018Domain Name System\u2019 c\u00fcmlesinin k\u0131saltmas\u0131 olan \u2018Etki Alan\u0131 Ad Sistemi\u2019dir.<\/span><\/p>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bir ba\u015fka deyi\u015fle genel veya yerel a\u011flar i\u00e7erisindeki telefon rehberi veya size hangi kitab\u0131n nerede oldu\u011funu s\u00f6yleyen bir k\u00fct\u00fcphane g\u00f6revlisidir. Bu rehber i\u00e7erisinde a\u011fa ba\u011fl\u0131 bilgisayarlar, servisler ve di\u011fer kaynaklar yer al\u0131r. Nas\u0131l ki telefon rehberlerinde bir girdinin ad\u0131 bir telefon numaras\u0131na kar\u015f\u0131l\u0131k geliyor ise <strong>DNS<\/strong> de ayn\u0131 bilgileri saklar ve yap\u0131land\u0131rma ile bizim belirledi\u011fimiz istemcilere sunar.<\/span><\/p>\n<p dir=\"ltr\"><span style=\"color: #000000;\">DNS, kaynaklar\u0131 \u00e7\u00f6z\u00fcmlerken telefon numaras\u0131 yerine a\u011fa ba\u011fl\u0131 her cihaza atanan ve say\u0131sal bir etiket olan IP adresini kullan\u0131r. IP adresleri versiyon 4 (IPV4 \u00f6rnek: 192.168.1.1) ve versiyon 6 (IPV6 \u00f6rnek : e3e2:f857:b292:7423:898d:ff86:<wbr>908e:ce4a) olarak iki \u00e7e\u015fittir. D\u00fc\u015f\u00fcnsenize 1000 k\u00fcs\u00fcr adet&nbsp; sunucunuz var ve bunlar\u0131n adreslerini her soran oldu\u011funda \u00e7ok k\u0131sa bir s\u00fcre i\u00e7erisinde s\u00f6ylemek zorundas\u0131n\u0131z ! DNS, insanlar\u0131 say\u0131s\u0131z IP adresini ak\u0131lda tutmak k\u00fclfetinden kurtaran bir yap\u0131d\u0131r.<\/span><\/p>\n<h2 dir=\"ltr\"><strong><span style=\"color: #000000;\">DNS Nas\u0131l \u00c7al\u0131\u015f\u0131r ?<\/span><\/strong><\/h2>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Basit olarak DNS \u00e7\u00f6z\u00fcmleme s\u00fcreci, bir bilgisayar ad\u0131n\u0131&nbsp; bir DNS sunucusu vas\u0131tas\u0131 ile bir IP adresine d\u00f6n\u00fc\u015ft\u00fcrme i\u015flemidir. \u00d6rnek olarak tamamen hayal \u00fcr\u00fcn\u00fc olan http:\/\/dnsnedir.com alan ad\u0131n\u0131 alal\u0131m. \u0130stemcinin (client)<\/span> <span style=\"color: #0000ff;\"><span style=\"color: #000000;\">http:\/\/dosya.dnsnedir.com<\/span> <\/span><span style=\"color: #000000;\">adresine gitmek istedi\u011fini varsayarsak, DNS \u00e7\u00f6z\u00fcmleme s\u00fcreci en yal\u0131n hali ile a\u015fa\u011f\u0131daki \u015fekilde ilerleyecektir.<\/span><\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">\u0130stemci DNS sunucusuna http:\/\/dosya.dnsnedir.com adresine gitmek istedi\u011fini ve bu bilgisayar ad\u0131n\u0131na sahip olan sunucusunun IP adresini sorar<\/span><\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">DNS sunucusu istemciye 192.168.1.2 adresini g\u00f6nderir (tabiki var ise !)<\/span><\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">\u0130stemci http:\/\/192.168.1.2 adresine y\u00f6nelir ve istedi\u011fi bilgiye ula\u015f\u0131r<\/span><\/p>\n<\/li>\n<\/ul>\n<h2 dir=\"ltr\"><strong><span style=\"color: #000000;\">DNS Kay\u0131tlar\u0131n\u0131n \u00c7e\u015fitleri<\/span><\/strong><\/h2>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Kullan\u0131m yerine g\u00f6re DNS kay\u0131tlar\u0131n\u0131n bir\u00e7ok \u00e7e\u015fidi var<\/span> (<span style=\"color: #0000ff;\"><a style=\"color: #0000ff;\" href=\"https:\/\/en.wikipedia.org\/wiki\/List_of_DNS_record_types\" target=\"_blank\" rel=\"noopener noreferrer\" data-saferedirecturl=\"https:\/\/www.google.com\/url?q=https:\/\/en.wikipedia.org\/wiki\/List_of_DNS_record_types&amp;source=gmail&amp;ust=1603781653709000&amp;usg=AFQjCNGtvVWcDw5pKImX551qUwK549w4HA\">https:\/\/en.wikipedia.org\/<wbr>wiki\/List_of_DNS_record_types<\/a><\/span>) <span style=\"color: #000000;\">ancak ben bu yaz\u0131da sadece genel DNS kay\u0131tlar\u0131na de\u011finece\u011fim.<\/span><\/p>\n<h3 dir=\"ltr\"><span style=\"color: #000000;\"><strong>SOA (Start of Authority) DNS Kayd\u0131<\/strong><\/span><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bu kay\u0131t bir DNS b\u00f6lgesi i\u00e7in hangi sunucunun cevaplar\u0131 vermekte yetkili oldu\u011funu belirler. \u00d6rnek vermek gerekir ise daha \u00f6nce \u00f6rnekte sordu\u011fumuz <\/span>dnsnedir.com <span style=\"color: #000000;\">DNS b\u00f6lgesi i\u00e7in SOA kayd\u0131 mesela <\/span>dns1.dnsnedir.com<span style=\"color: #000000;\"> sunucusuna \u00e7\u00f6z\u00fcmlenir.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">NS (Nameserver) DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Verilen bir DNS b\u00f6lgesinde kullan\u0131lacak yetkili ad sunucular\u0131n\u0131 belirlemek i\u00e7in kullan\u0131l\u0131r.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">MX (Mail Exchange) DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bu kay\u0131t istemciyi bizim faraziye \u00f6rne\u011fimiz<\/span> dnsnedir.com <span style=\"color: #000000;\">alan ad\u0131m\u0131z i\u00e7erisindeki mesaj aktar\u0131m arac\u0131lar\u0131n\u0131n listesiyle e\u015fle\u015ftirir. Bir ba\u015fka deyi\u015fle e-posta sunucular\u0131n\u0131 d\u0131\u015far\u0131dan gelen istemciye s\u00f6yler.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">A DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">En yayg\u0131n olarak bilgisayar adlar\u0131n\u0131 IP adresiyle e\u015flemek i\u00e7in kullan\u0131l\u0131r.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">AAAA DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">A DNS kayd\u0131n\u0131n IPV6 standard\u0131nda olan halidir.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">PTR DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bu kay\u0131t ters DNS kayd\u0131 olarak da bilinir ve \u015fimdiye kadar anlatt\u0131\u011f\u0131m\u0131z bilgisayar ad\u0131 -&gt; IP Adresi d\u00f6n\u00fc\u015f\u00fcm\u00fcn\u00fcn tam tersini yapar. \u0130stemci burada IP adresi ile gelir ve DNS sunucu i\u00e7erisinde yer alan bilgisayar ad\u0131na ula\u015f\u0131r, tabiki var ise !<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">CNAME DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bu kay\u0131t bir DNS A kayd\u0131na takma ad vermek i\u00e7in kullan\u0131l\u0131r. Mesela kullan\u0131c\u0131lar yanl\u0131\u015fl\u0131kla<\/span> http:\/\/dosyalar.dnsnedir.com <span style=\"color: #000000;\">yazarlarsa<\/span> http:\/\/dosya.dnsnedir.com <span style=\"color: #000000;\">adresine yine de y\u00f6nlendirilsinler isterseniz CNAME DNS kayd\u0131n\u0131 kullanmal\u0131s\u0131n\u0131z.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">SRV (Service Record) DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bu kay\u0131t istemcilerin DNS sunucudan hizmet konumlar\u0131n\u0131 alabilmelerini sa\u011flar. \u00d6rnek vermek gerekir ise bir SIP sunucusu i\u00e7in a\u015fa\u011f\u0131daki \u015fekild<\/span><span style=\"color: #000000;\">e bir DNS SRV kayd\u0131na ihtiya\u00e7 vard\u0131r.<\/span><\/p>\n<p dir=\"ltr\"><span style=\"color: #000000;\">_sip._tcp.dnsnedir.com. 86400 IN SRV 0 5 5060 sipserver.dnsnedir.com.<\/span><\/p>\n<h3 dir=\"ltr\"><strong><span style=\"color: #000000;\">TXT DNS Kayd\u0131<\/span><\/strong><\/h3>\n<p dir=\"ltr\"><span style=\"color: #000000;\">TXT kay\u0131tlar\u0131 birden fazla i\u015f yapmak i\u00e7in kullan\u0131l\u0131r. \u00d6nceleri sadece istemcilere metin iletmek i\u00e7in kullan\u0131lsa da daha sonra bu kayd\u0131n esnekli\u011fi sayesinde makine-okunabilir-veri ta\u015f\u0131mak i\u00e7in kullan\u0131l\u0131yor. Mesela eposta sunucular\u0131n\u0131n spam ile sava\u015fmas\u0131nda, bir epostan\u0131n hakikaten \u00e7\u0131kt\u0131\u011f\u0131 g\u00f6sterilen (eposta header bilgisinde) etki alan\u0131ndan gelip gelmedi\u011finin kontrolleri gibi de\u011fi\u015fik i\u015flerde \u00e7ok i\u015fe yarar. Bu kay\u0131tlara da DKIM, DMARC ve SPF olarak de\u011finmi\u015f olay\u0131m. Bu kay\u0131tlarla ilgili bilgileri ba\u015fka g\u00f6nderilerde yazaca\u011f\u0131m.<\/span><\/p>\n<h2 dir=\"ltr\"><strong><span style=\"color: #000000;\">A\u00e7\u0131k Kaynak DNS Sunucular\u0131 nelerdir ?<\/span><\/strong><\/h2>\n<p dir=\"ltr\"><span style=\"color: #000000;\">A\u00e7\u0131k kaynak d\u00fcnyas\u0131nda en \u00e7ok kullan\u0131lan DNS sunucusu servisi <a style=\"color: #000000;\" href=\"https:\/\/www.isc.org\/bind\/\" target=\"_blank\" rel=\"noopener noreferrer\" data-saferedirecturl=\"https:\/\/www.google.com\/url?q=https:\/\/www.isc.org\/bind\/&amp;source=gmail&amp;ust=1603781653709000&amp;usg=AFQjCNHbHWC0oCxBHV_X-c628OZrtQp4Mw\"><span style=\"color: #0000ff;\">BIND<\/span><\/a> (Berkeley Internet Name Domain) servisidir. Hemen hemen b\u00fct\u00fcn Linux da\u011f\u0131t\u0131mlar\u0131n\u0131n paket y\u00f6neticileri vas\u0131tas\u0131 ile kurulabilir veya kald\u0131r\u0131labilir. Konteyner mimarisi kullananlara \u00f6zel Docker \u00fczerinde ko\u015fmas\u0131 i\u00e7in haz\u0131r docker imajlar\u0131 bile var (bak\u0131n\u0131z : <span style=\"color: #0000ff;\"><a style=\"color: #0000ff;\" href=\"https:\/\/hub.docker.com\/r\/internetsystemsconsortium\/bind9\" target=\"_blank\" rel=\"noopener noreferrer\" data-saferedirecturl=\"https:\/\/www.google.com\/url?q=https:\/\/hub.docker.com\/r\/internetsystemsconsortium\/bind9&amp;source=gmail&amp;ust=1603781653709000&amp;usg=AFQjCNGWaIgcd60oa1XSbntqTN2WOKFngg\">https:\/\/hub.docker.com\/r\/<wbr>internetsystemsconsortium\/<wbr>bind9<\/a><\/span> ). Di\u011fer DNS sunucu servislerinden baz\u0131lar\u0131n\u0131 ise a\u015fa\u011f\u0131da listeledim.<\/span><\/p>\n<ul>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">PowerDNS<\/span><\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">KnotDNS<\/span><\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">CoreDNS (kubernetes i\u00e7erisindeki varsay\u0131lan DNS sunucusudur)<\/span><\/p>\n<\/li>\n<li dir=\"ltr\">\n<p dir=\"ltr\"><span style=\"color: #000000;\">&#8230;<\/span><\/p>\n<\/li>\n<\/ul>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Yukar\u0131da sayd\u0131\u011f\u0131m DNS servislerinin (sunucular\u0131n\u0131n) her birinin di\u011ferlerine g\u00f6re art\u0131lar\u0131 ve eksileri var ancak bunlar aras\u0131nda \u00f6zellikleri ve kullan\u0131m kolayl\u0131\u011f\u0131 a\u00e7\u0131s\u0131ndan en yayg\u0131n olarak kullanlan BIND\u2019d\u0131r.<\/span><\/p>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Elimden gelen en yal\u0131n haliyle DNS, DNS \u00e7\u00f6z\u00fcmleme s\u00fcreci, DNS kay\u0131t tipleri ve kullan\u0131labilecek DNS sunucular\u0131n\u0131 anlatt\u0131m. Art\u0131k DNS\u2019in ne i\u015fe yarad\u0131\u011f\u0131n\u0131 ve basit olarak nas\u0131l \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 biliyorsunuz ! Bu noktadan sonra merak etmek, okumak, \u00f6\u011frenmek, denemek, sorunla kar\u015f\u0131la\u015fmak, sorunu tespit etmek, gidermek ve arkan\u0131za yaslan\u0131p \u2018ben bu i\u015fi anlad\u0131m\u2019 demek size kal\u0131yor ! <\/span><\/p>\n<p dir=\"ltr\"><span style=\"color: #000000;\">Bol a\u00e7\u0131k kaynakl\u0131 g\u00fcnler !<\/span><\/p>","protected":false},"excerpt":{"rendered":"<p>DNS Ingilizce \u2018Domain Name System\u2019 c\u00fcmlesinin k\u0131saltmas\u0131 olan \u2018Etki Alan\u0131 Ad Sistemi\u2019dir. Bir ba\u015fka deyi\u015fle genel veya yerel a\u011flar i\u00e7erisindeki telefon rehberi veya size hangi kitab\u0131n nerede oldu\u011funu s\u00f6yleyen bir k\u00fct\u00fcphane g\u00f6revlisidir. Bu rehber i\u00e7erisinde a\u011fa ba\u011fl\u0131 bilgisayarlar, servisler ve&#8230;<\/p>","protected":false},"author":12,"featured_media":22104,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[76,45],"tags":[61],"class_list":["post-17571","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-linux","category-yazi","tag-linux"],"_links":{"self":[{"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/posts\/17571","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/comments?post=17571"}],"version-history":[{"count":0,"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/posts\/17571\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/media\/22104"}],"wp:attachment":[{"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/media?parent=17571"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/categories?post=17571"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/profelis.com.tr\/en\/wp-json\/wp\/v2\/tags?post=17571"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}