{"id":1504,"date":"2025-11-07T19:23:47","date_gmt":"2025-11-07T16:23:47","guid":{"rendered":"https:\/\/www.dchost.com\/blog\/gelismis-dns-yonlendirme-nasil-akillanir-cloudflare-route-53-ile-cografi-agirlikli-ve-split%e2%80%91horizon-uzerine-sicacik-bir-yolculuk\/"},"modified":"2025-11-07T19:23:47","modified_gmt":"2025-11-07T16:23:47","slug":"gelismis-dns-yonlendirme-nasil-akillanir-cloudflare-route-53-ile-cografi-agirlikli-ve-split%e2%80%91horizon-uzerine-sicacik-bir-yolculuk","status":"publish","type":"post","link":"https:\/\/www.dchost.com\/blog\/gelismis-dns-yonlendirme-nasil-akillanir-cloudflare-route-53-ile-cografi-agirlikli-ve-split%e2%80%91horizon-uzerine-sicacik-bir-yolculuk\/","title":{"rendered":"Geli\u015fmi\u015f DNS Y\u00f6nlendirme Nas\u0131l Ak\u0131llan\u0131r? Cloudflare\/Route 53 ile Co\u011frafi, A\u011f\u0131rl\u0131kl\u0131 ve Split\u2011Horizon \u00dczerine S\u0131cac\u0131k Bir Yolculuk"},"content":{"rendered":"<div class=\"dchost-blog-content-wrapper\"><div id=\"toc_container\" class=\"toc_transparent no_bullets\"><p class=\"toc_title\">\u0130&ccedil;indekiler<\/p><ul class=\"toc_list\"><li><a href=\"#Ofiste_Baslayan_Kucuk_Bir_DNS_Macerasi\"><span class=\"toc_number toc_depth_1\">1<\/span> Ofiste Ba\u015flayan K\u00fc\u00e7\u00fck Bir DNS Maceras\u0131<\/a><\/li><li><a href=\"#DNSin_Sahne_Arkasi_Neden_Bazen_Beklediginizi_Alamazsiniz\"><span class=\"toc_number toc_depth_1\">2<\/span> DNS\u2019in Sahne Arkas\u0131: Neden Bazen Bekledi\u011finizi Alamazs\u0131n\u0131z?<\/a><ul><li><a href=\"#Resolverlar_TTLler_ve_o_meshur_onbellek\"><span class=\"toc_number toc_depth_2\">2.1<\/span> Resolver\u2019lar, TTL\u2019ler ve o me\u015fhur \u00f6nbellek<\/a><\/li><li><a href=\"#Yuzdeler_neden_birebir_kullaniciya_yansimaz\"><span class=\"toc_number toc_depth_2\">2.2<\/span> Y\u00fczdeler neden birebir kullan\u0131c\u0131ya yans\u0131maz?<\/a><\/li><\/ul><\/li><li><a href=\"#Cografi_DNS_Nereden_Geliyorsun_Sorusu_ve_Nazik_Yonlendirme\"><span class=\"toc_number toc_depth_1\">3<\/span> Co\u011frafi DNS: \u201cNereden Geliyorsun?\u201d Sorusu ve Nazik Y\u00f6nlendirme<\/a><ul><li><a href=\"#Ulke_bolge_sehir_Ne_kadar_ince_ayar\"><span class=\"toc_number toc_depth_2\">3.1<\/span> \u00dclke, b\u00f6lge, \u015fehir\u2026 Ne kadar ince ayar?<\/a><\/li><li><a href=\"#EDNS_ipucu_ve_test_ederken_dikkat\"><span class=\"toc_number toc_depth_2\">3.2<\/span> EDNS ipucu ve test ederken dikkat<\/a><\/li><\/ul><\/li><li><a href=\"#Agirlikli_Weighted_DNS_Trafigi_Yumusacik_Bolmenin_En_Tatli_Yolu\"><span class=\"toc_number toc_depth_1\">4<\/span> A\u011f\u0131rl\u0131kl\u0131 (Weighted) DNS: Trafi\u011fi Yumu\u015fac\u0131k B\u00f6lmenin En Tatl\u0131 Yolu<\/a><ul><li><a href=\"#Canary_maviyesil_ve_nazik_gecisler\"><span class=\"toc_number toc_depth_2\">4.1<\/span> Canary, mavi\u2011ye\u015fil ve nazik ge\u00e7i\u015fler<\/a><\/li><li><a href=\"#Gercek_yuzde_ile_hissedilen_yuzde_arasindaki_fark\"><span class=\"toc_number toc_depth_2\">4.2<\/span> Ger\u00e7ek y\u00fczde ile hissedilen y\u00fczde aras\u0131ndaki fark<\/a><\/li><li><a href=\"#Saglik_kontrolleri_ve_kirilinca_dusmesin_temennisi\"><span class=\"toc_number toc_depth_2\">4.3<\/span> Sa\u011fl\u0131k kontrolleri ve \u201ck\u0131r\u0131l\u0131nca d\u00fc\u015fmesin\u201d temennisi<\/a><\/li><\/ul><\/li><li><a href=\"#SplitHorizon_Icerden_Bakinca_Baska_Disardan_Bakinca_Baska_Dunya\"><span class=\"toc_number toc_depth_1\">5<\/span> Split\u2011Horizon: \u0130\u00e7erden Bak\u0131nca Ba\u015fka, D\u0131\u015fardan Bak\u0131nca Ba\u015fka D\u00fcnya<\/a><ul><li><a href=\"#Kurumsal_ag_VPN_ve_ozel_bolgeler\"><span class=\"toc_number toc_depth_2\">5.1<\/span> Kurumsal a\u011f, VPN ve \u00f6zel b\u00f6lgeler<\/a><\/li><li><a href=\"#Iki_gercek_tek_alan_adi\"><span class=\"toc_number toc_depth_2\">5.2<\/span> \u0130ki ger\u00e7ek, tek alan ad\u0131<\/a><\/li><\/ul><\/li><li><a href=\"#Uctan_Uca_Kurgular_Cografi_Weighted_SplitHorizon_Birlikte_Nasil_Akar\"><span class=\"toc_number toc_depth_1\">6<\/span> U\u00e7tan Uca Kurgular: Co\u011frafi + Weighted + Split\u2011Horizon Birlikte Nas\u0131l Akar?<\/a><ul><li><a href=\"#Senaryoyu_canli_dusunelim\"><span class=\"toc_number toc_depth_2\">6.1<\/span> Senaryoyu canl\u0131 d\u00fc\u015f\u00fcnelim<\/a><\/li><li><a href=\"#TTL_taktigi_ve_kucuk_ritueller\"><span class=\"toc_number toc_depth_2\">6.2<\/span> TTL takti\u011fi ve k\u00fc\u00e7\u00fck rit\u00fceller<\/a><\/li><li><a href=\"#IPv6yi_unutmamak\"><span class=\"toc_number toc_depth_2\">6.3<\/span> IPv6\u2019y\u0131 unutmamak<\/a><\/li><li><a href=\"#Uygulama_katmanini_da_dusunmek\"><span class=\"toc_number toc_depth_2\">6.4<\/span> Uygulama katman\u0131n\u0131 da d\u00fc\u015f\u00fcnmek<\/a><\/li><\/ul><\/li><li><a href=\"#Test_Gozlem_ve_Sorun_Giderme_Nerede_Ne_Olduyu_Sakince_Bulmak\"><span class=\"toc_number toc_depth_1\">7<\/span> Test, G\u00f6zlem ve Sorun Giderme: \u201cNerede Ne Oldu?\u201dyu Sakince Bulmak<\/a><ul><li><a href=\"#Tek_bir_aracla_degil_birkac_pencereden_bakmak\"><span class=\"toc_number toc_depth_2\">7.1<\/span> Tek bir ara\u00e7la de\u011fil, birka\u00e7 pencereden bakmak<\/a><\/li><li><a href=\"#Dokumantasyonlar_ve_sakin_aksam_okumalari\"><span class=\"toc_number toc_depth_2\">7.2<\/span> Dok\u00fcmantasyonlar ve sakin ak\u015fam okumalar\u0131<\/a><\/li><\/ul><\/li><li><a href=\"#Kucuk_Tuzaklar_ve_Nazik_Cozumler\"><span class=\"toc_number toc_depth_1\">8<\/span> K\u00fc\u00e7\u00fck Tuzaklar ve Nazik \u00c7\u00f6z\u00fcmler<\/a><ul><li><a href=\"#Negatif_onbellek_ve_yok_cevabi\"><span class=\"toc_number toc_depth_2\">8.1<\/span> Negatif \u00f6nbellek ve \u201cyok\u201d cevab\u0131<\/a><\/li><li><a href=\"#Isimlendirme_ve_okunabilirlik\"><span class=\"toc_number toc_depth_2\">8.2<\/span> \u0130simlendirme ve okunabilirlik<\/a><\/li><li><a href=\"#Once_temel_taslar\"><span class=\"toc_number toc_depth_2\">8.3<\/span> \u00d6nce temel ta\u015flar<\/a><\/li><\/ul><\/li><li><a href=\"#Kapanis_Yumusak_Gecislerin_ve_Dogru_Adreslerin_Mutlulugu\"><span class=\"toc_number toc_depth_1\">9<\/span> Kapan\u0131\u015f: Yumu\u015fak Ge\u00e7i\u015flerin ve Do\u011fru Adreslerin Mutlulu\u011fu<\/a><\/li><\/ul><\/div>\n<h2 id=\"section-1\"><span id=\"Ofiste_Baslayan_Kucuk_Bir_DNS_Macerasi\">Ofiste Ba\u015flayan K\u00fc\u00e7\u00fck Bir DNS Maceras\u0131<\/span><\/h2>\n<p>Hi\u00e7 ba\u015f\u0131n\u0131za geldi mi? Hani her \u015feyin yolunda oldu\u011funu d\u00fc\u015f\u00fcnd\u00fc\u011f\u00fcn\u00fcz bir sabahta, kampanya sayfas\u0131 bir anda ate\u015f al\u0131r ve kuzeyde ya\u015fayan kullan\u0131c\u0131lar\u0131n\u0131z \u0131\u015f\u0131k h\u0131z\u0131nda a\u00e7arken, g\u00fcneydeki ziyaret\u00e7iler telefonlar\u0131n\u0131n ekran\u0131nda d\u00f6n\u00fcp duran bir y\u00fckleme simgesine bakakal\u0131r. O g\u00fcn, ofiste kahvemi al\u0131p loglara dald\u0131\u011f\u0131mda, \u201cBunu DNS ile tatl\u0131 tatl\u0131 y\u00f6nlendirmeden nas\u0131l \u00e7\u00f6zeriz?\u201d diye d\u00fc\u015f\u00fcnd\u00fcm. \u00c7\u00fcnk\u00fc <strong>geli\u015fmi\u015f DNS y\u00f6nlendirme<\/strong> sadece kay\u0131t eklemek de\u011fil; kullan\u0131c\u0131y\u0131 do\u011fru yere, do\u011fru anda ve do\u011fru a\u011f\u0131rl\u0131kla g\u00f6ndermek demek.<\/p>\n<p>Bu yaz\u0131da, Cloudflare ve Route 53 \u00fczerinde <strong>co\u011frafi<\/strong> ve <strong>a\u011f\u0131rl\u0131kl\u0131 (weighted)<\/strong> DNS senaryolar\u0131n\u0131, \u00fczerine bir de <strong>split\u2011horizon<\/strong> yakla\u015f\u0131m\u0131n\u0131 ekleyerek sindire sindire konu\u015faca\u011f\u0131z. Mesela \u015f\u00f6yle d\u00fc\u015f\u00fcn\u00fcn: Trafi\u011fin bir k\u0131sm\u0131n\u0131 yeni versiyona nazik\u00e7e ta\u015f\u0131mak, Avrupa\u2019y\u0131 Frankfurt\u2019a, Ortado\u011fu\u2019yu \u0130stanbul\u2019a ak\u0131tmak, \u015firket i\u00e7indeyken ba\u015fka, d\u0131\u015far\u0131dayken bamba\u015fka adres g\u00f6rmek. Hepsi m\u00fcmk\u00fcn. Yolda k\u00fc\u00e7\u00fck p\u00fcf noktalar\u0131 da payla\u015faca\u011f\u0131m. Biraz konu d\u0131\u015f\u0131na dalaca\u011f\u0131z, ama her d\u00f6n\u00fc\u015fte cebimiz daha dolu olacak.<\/p>\n<h2 id=\"section-2\"><span id=\"DNSin_Sahne_Arkasi_Neden_Bazen_Beklediginizi_Alamazsiniz\">DNS\u2019in Sahne Arkas\u0131: Neden Bazen Bekledi\u011finizi Alamazs\u0131n\u0131z?<\/span><\/h2>\n<h3><span id=\"Resolverlar_TTLler_ve_o_meshur_onbellek\">Resolver\u2019lar, TTL\u2019ler ve o me\u015fhur \u00f6nbellek<\/span><\/h3>\n<p>DNS, sahnenin arkas\u0131nda duran sessiz bir kahraman. Bir sorgu yola \u00e7\u0131kt\u0131\u011f\u0131nda, yol \u00fcst\u00fcnde duran \u00e7\u00f6z\u00fcmleyiciler onu ellerinden geldi\u011fince h\u0131zland\u0131r\u0131r. Bunun bedeli de <strong>\u00f6nbellek<\/strong>. Koydu\u011funuz bir kayd\u0131 yaymak bazen saniyeler s\u00fcrer, bazen beklenmedik \u015fekilde dakikalara uzar. Mesela bir A kayd\u0131n\u0131 de\u011fi\u015ftirdiniz, fakat baz\u0131 kullan\u0131c\u0131larda eski IP \u00e7al\u0131\u015fmaya devam ediyor. Su\u00e7 \u00e7o\u011fu zaman <strong>TTL<\/strong> ayar\u0131nda. \u00c7ok uzun TTL rahat ettirir, ama ani de\u011fi\u015fikliklerde sizi yava\u015flat\u0131r. \u00c7ok k\u0131sa TTL ise herkese s\u0131k s\u0131k \u201cyeni ne var?\u201d sorusunu sorar, bu da gereksiz g\u00fcr\u00fclt\u00fc ve maliyet demek.<\/p>\n<h3><span id=\"Yuzdeler_neden_birebir_kullaniciya_yansimaz\">Y\u00fczdeler neden birebir kullan\u0131c\u0131ya yans\u0131maz?<\/span><\/h3>\n<p>\u201cY\u00fczde 10\u2019u yeni ortama alal\u0131m\u201d dedi\u011finizde, asl\u0131nda \u00e7\u00f6z\u00fcmleyici seviyesinde bir da\u011f\u0131l\u0131m yapm\u0131\u015f olursunuz. Yani payla\u015ft\u0131rma \u00e7o\u011fu zaman <strong>kullan\u0131c\u0131<\/strong> de\u011fil, <strong>resolver<\/strong> baz\u0131nda. \u015eirket a\u011f\u0131nda tek bir resolver varsa, o ofisin tamam\u0131 ayn\u0131 cevab\u0131 alabilir. Bu da bazen \u015fa\u015f\u0131rt\u0131c\u0131 sonu\u00e7lar do\u011furur. Y\u00fczde 10 beklerken, belli bir lokasyonda y\u00fczde 0 veya y\u00fczde 100 g\u00f6rebilirsiniz. Bu do\u011fald\u0131r. \u00d6nemli olan, bunun \u00fczerine g\u00f6zlem yap\u0131p ayarlar\u0131 nazik\u00e7e \u00e7ekip \u00e7evirmek.<\/p>\n<h2 id=\"section-3\"><span id=\"Cografi_DNS_Nereden_Geliyorsun_Sorusu_ve_Nazik_Yonlendirme\">Co\u011frafi DNS: \u201cNereden Geliyorsun?\u201d Sorusu ve Nazik Y\u00f6nlendirme<\/span><\/h2>\n<h3><span id=\"Ulke_bolge_sehir_Ne_kadar_ince_ayar\">\u00dclke, b\u00f6lge, \u015fehir\u2026 Ne kadar ince ayar?<\/span><\/h3>\n<p>Co\u011frafi y\u00f6nlendirme, kabaca \u201cbu sorgu nereden geliyor\u201d diye bak\u0131p en yak\u0131n veya en uygun hedefi d\u00f6nd\u00fcrmek. Cloudflare\u2019da bunu <strong>geo steering<\/strong> mant\u0131\u011f\u0131yla, Route 53\u2019te ise <strong>geolocation<\/strong> veya <strong>geoproximity<\/strong> politikalar\u0131yla d\u00fc\u015f\u00fcnebilirsiniz. Bir kampanya d\u00f6neminde Avrupa trafi\u011fini Frankfurt\u2019a, Kuzey Amerika\u2019y\u0131 ise bir Do\u011fu bir Bat\u0131 k\u0131y\u0131s\u0131nda nazik\u00e7e dengeleyerek g\u00f6ndermek sahada \u00e7ok i\u015fimi g\u00f6rd\u00fc. Mobil operat\u00f6rlerin ve VPN\u2019lerin co\u011frafi i\u015faretleri ara s\u0131ra \u015fa\u015f\u0131rtabildi\u011fini de unutmay\u0131n. Bu y\u00fczden kurgu ne kadar ak\u0131ll\u0131 olursa olsun, her zaman k\u00fc\u00e7\u00fck bir pay emniyet b\u0131rakmak iyi geliyor.<\/p>\n<h3><span id=\"EDNS_ipucu_ve_test_ederken_dikkat\">EDNS ipucu ve test ederken dikkat<\/span><\/h3>\n<p>Baz\u0131 \u00e7\u00f6z\u00fcmleyiciler, istemcinin ger\u00e7ek lokasyonuna dair k\u00fc\u00e7\u00fck ipu\u00e7lar\u0131 ta\u015f\u0131r. Buna teknik tarafta \u201cistemcinin konum ipucu\u201d gibi d\u00fc\u015f\u00fcnebilirsiniz. Test ederken farkl\u0131 <strong>\u00e7\u0131kar noktas\u0131na sahip resolver\u2019lar<\/strong> \u00fczerinden sorgu yapmak i\u015fe yarar. Tek bir internet ba\u011flant\u0131s\u0131ndan bak\u0131p \u201ctamamd\u0131r\u201d demek, kendimizi kand\u0131rmak olur. Birka\u00e7 farkl\u0131 \u015fehirden, bir iki <a href=\"https:\/\/www.dchost.com\/tr\/bulut-sunucu\">bulut sunucu<\/a>dan ve m\u00fcmk\u00fcnse mobil a\u011fdan bak\u0131nca resim tamamlan\u0131r. Bu a\u00e7\u0131dan Cloudflare\u2019\u0131n <a href=\"https:\/\/developers.cloudflare.com\/load-balancing\/understand\/steering-methods\/geo-steering\/\" rel=\"nofollow noopener\" target=\"_blank\">geo steering anlat\u0131m\u0131<\/a> ile Route 53\u2019\u00fcn <a href=\"https:\/\/docs.aws.amazon.com\/Route53\/latest\/DeveloperGuide\/routing-policy.html\" rel=\"nofollow noopener\" target=\"_blank\">y\u00f6nlendirme politikalar\u0131 sayfas\u0131n\u0131<\/a> sakin bir ak\u015fam okumak, kavramlar\u0131 yerine oturtuyor.<\/p>\n<h2 id=\"section-4\"><span id=\"Agirlikli_Weighted_DNS_Trafigi_Yumusacik_Bolmenin_En_Tatli_Yolu\">A\u011f\u0131rl\u0131kl\u0131 (Weighted) DNS: Trafi\u011fi Yumu\u015fac\u0131k B\u00f6lmenin En Tatl\u0131 Yolu<\/span><\/h2>\n<h3><span id=\"Canary_maviyesil_ve_nazik_gecisler\">Canary, mavi\u2011ye\u015fil ve nazik ge\u00e7i\u015fler<\/span><\/h3>\n<p>Yeni bir s\u00fcr\u00fcme y\u00fczde 5, sonra 10, sonra 25 derken nazik\u00e7e ge\u00e7mek istiyorsan\u0131z, <strong>a\u011f\u0131rl\u0131kl\u0131 DNS<\/strong> nefis bir y\u00f6ntem. Mesela \u015f\u00f6yle d\u00fc\u015f\u00fcn\u00fcn: \u00dcretimde \u00e7al\u0131\u015fan bir uygulaman\u0131z var. Yeni s\u00fcr\u00fcm\u00fc yan tarafta haz\u0131r ettiniz. \u00d6nce k\u00fc\u00e7\u00fck bir kitleyi yeni tarafa al\u0131yorsunuz. Loglar temizse, hatalar sakinse, de\u011feri art\u0131r\u0131yorsunuz. Bir sorun \u00e7\u0131karsa a\u011f\u0131rl\u0131\u011f\u0131 eski s\u00fcr\u00fcme geri kayd\u0131rmak bir t\u0131k kadar yak\u0131n. Bu yakla\u015f\u0131m, geceyar\u0131s\u0131 tam kesinti yerine, g\u00fcnd\u00fcz saatlerinde yumu\u015fak bir ak\u0131\u015fla ilerlemeyi sa\u011fl\u0131yor.<\/p>\n<h3><span id=\"Gercek_yuzde_ile_hissedilen_yuzde_arasindaki_fark\">Ger\u00e7ek y\u00fczde ile hissedilen y\u00fczde aras\u0131ndaki fark<\/span><\/h3>\n<p>Burada en s\u0131k duydu\u011fum soru \u015fu: \u201cY\u00fczde 10 dedim, ama ekip tamam\u0131 yeni s\u00fcr\u00fcm\u00fc g\u00f6r\u00fcyor.\u201d Az \u00f6nce konu\u015ftu\u011fumuz gibi, bu \u00e7o\u011fu zaman <strong>\u00e7\u00f6z\u00fcmleyici mercek etkisi<\/strong>. Ofiste tek DNS \u00e7\u0131k\u0131\u015f\u0131 varsa, oradaki herkes ayn\u0131 cevab\u0131 alabilir. \u00c7\u00f6z\u00fcm, test ve \u00f6l\u00e7\u00fcm\u00fc <strong>farkl\u0131 resolver\u2019lar<\/strong> \u00fczerinden yapmak ve kararlar\u0131 aceleye getirmemek. Ayr\u0131ca TTL\u2019leri ge\u00e7i\u015f d\u00f6neminde makul bir s\u00fcre k\u0131saltmak, ani geri d\u00f6n\u00fc\u015f gerekti\u011finde hayat kurtar\u0131yor.<\/p>\n<h3><span id=\"Saglik_kontrolleri_ve_kirilinca_dusmesin_temennisi\">Sa\u011fl\u0131k kontrolleri ve \u201ck\u0131r\u0131l\u0131nca d\u00fc\u015fmesin\u201d temennisi<\/span><\/h3>\n<p>Weighted DNS\u2019in yan\u0131nda bir <strong>sa\u011fl\u0131k kontrol\u00fc<\/strong> mekanizmas\u0131 e\u015flik etti\u011finde, hedeflerden biri sorun ya\u015farsa trafik kendili\u011finden di\u011ferine kay\u0131yor. Cloudflare ve Route 53\u2019te farkl\u0131 adlarla an\u0131lsa da mant\u0131k ayn\u0131: u\u00e7lar\u0131n nabz\u0131n\u0131 tutmak. Tek hat\u0131rlatma: DNS, uygulama katman\u0131ndaki hatalar\u0131 an\u0131nda g\u00f6rmez. Bir endpoint \u201cya\u015f\u0131yor\u201d gibi g\u00f6r\u00fcn\u00fcp, uygulama tarafta hata veriyor olabilir. O y\u00fczden uygulama sa\u011fl\u0131\u011f\u0131n\u0131 da \u00f6l\u00e7en u\u00e7lar eklemek tatl\u0131 bir sigorta.<\/p>\n<h2 id=\"section-5\"><span id=\"SplitHorizon_Icerden_Bakinca_Baska_Disardan_Bakinca_Baska_Dunya\">Split\u2011Horizon: \u0130\u00e7erden Bak\u0131nca Ba\u015fka, D\u0131\u015fardan Bak\u0131nca Ba\u015fka D\u00fcnya<\/span><\/h2>\n<h3><span id=\"Kurumsal_ag_VPN_ve_ozel_bolgeler\">Kurumsal a\u011f, VPN ve \u00f6zel b\u00f6lgeler<\/span><\/h3>\n<p>Split\u2011horizon, ayn\u0131 alan ad\u0131n\u0131n <strong>i\u00e7eriden<\/strong> farkl\u0131, <strong>d\u0131\u015far\u0131dan<\/strong> farkl\u0131 cevaplar vermesi. \u015eirket i\u00e7indeyken \u201capp.example.com\u201d \u00f6zel IP\u2019ye \u00e7\u00f6z\u00fcls\u00fcn, d\u0131\u015far\u0131dayken ise d\u0131\u015f y\u00fcze baks\u0131n gibi d\u00fc\u015f\u00fcnebilirsiniz. Route 53\u2019te <strong>\u00f6zel bar\u0131nd\u0131rma b\u00f6lgeleri<\/strong> bu i\u015fi do\u011fal kar\u015f\u0131l\u0131yor. Detaylar\u0131 merak edenler i\u00e7in AWS\u2019nin <a href=\"https:\/\/docs.aws.amazon.com\/Route53\/latest\/DeveloperGuide\/hosted-zones-private.html\" rel=\"nofollow noopener\" target=\"_blank\">private hosted zone sayfas\u0131<\/a> gayet ak\u0131c\u0131. Cloudflare taraf\u0131nda da \u00f6zel a\u011flar ve t\u00fcnellerle benzer desenler kurulabiliyor; burada kilit nokta, istemcinin nereden geldi\u011fini tan\u0131yacak bir kap\u0131 aralamak.<\/p>\n<h3><span id=\"Iki_gercek_tek_alan_adi\">\u0130ki ger\u00e7ek, tek alan ad\u0131<\/span><\/h3>\n<p>Split\u2011horizon kurarken en b\u00fcy\u00fck risk, <strong>kay\u0131t ayr\u0131\u015fmas\u0131<\/strong>. \u0130\u00e7 b\u00f6lgede g\u00fcncellemeyi yapt\u0131n\u0131z ama d\u0131\u015f\u0131 unuttunuz, veya tam tersi. Bir g\u00fcn staging\u2019e girmeniz gerekirken prod\u2019a ba\u011flan\u0131rs\u0131n\u0131z. Bu y\u00fczden kay\u0131tlar\u0131n \u201ctek bir kaynaktan y\u00f6netilmesi\u201d i\u00e7in k\u00fc\u00e7\u00fck bir rit\u00fcel olu\u015fturmak iyi oluyor. Adland\u0131rma standard\u0131, de\u011fi\u015fiklik listesi ve pratik bir g\u00f6zden ge\u00e7irme. K\u00fc\u00e7\u00fck g\u00f6r\u00fcnen ama b\u00fcy\u00fck kazalar \u00f6nleyen al\u0131\u015fkanl\u0131klar.<\/p>\n<p>Bu arada isim sunucular\u0131n\u0131z\u0131 kendiniz y\u00f6netiyorsan\u0131z ve d\u0131\u015f d\u00fcnyaya do\u011fru kimlik bilgisi vermek istiyorsan\u0131z, <a href=\"https:\/\/www.dchost.com\/blog\/ozel-ad-sunucusu-ve-glue-record-nasil-kurulur-kendi-dnsine-adim-adim-yolculuk\/\">kendi ad sunucunuzu ve glue record\u2019lar\u0131n\u0131z\u0131 kurmak<\/a> \u00fczerine anlatt\u0131\u011f\u0131m ad\u0131mlar ho\u015f bir ba\u015flang\u0131\u00e7 olabilir. Temel ta\u015flar yerindeyse, split\u2011horizon ve geli\u015fmi\u015f politikalar daha g\u00fcvenli y\u00fcr\u00fcyor.<\/p>\n<h2 id=\"section-6\"><span id=\"Uctan_Uca_Kurgular_Cografi_Weighted_SplitHorizon_Birlikte_Nasil_Akar\">U\u00e7tan Uca Kurgular: Co\u011frafi + Weighted + Split\u2011Horizon Birlikte Nas\u0131l Akar?<\/span><\/h2>\n<h3><span id=\"Senaryoyu_canli_dusunelim\">Senaryoyu canl\u0131 d\u00fc\u015f\u00fcnelim<\/span><\/h3>\n<p>Diyelim uygulaman\u0131z \u00fc\u00e7 b\u00f6lgede \u00e7al\u0131\u015f\u0131yor: Frankfurt, \u0130stanbul ve Virginia. Avrupa trafi\u011fini a\u011f\u0131rl\u0131kl\u0131 olarak Frankfurt\u2019a, Ortado\u011fu\u2019yu \u0130stanbul\u2019a, Kuzey Amerika\u2019y\u0131 Virginia\u2019ya ak\u0131tmak istiyorsunuz. \u00dcst\u00fcne, yeni s\u00fcr\u00fcm\u00fc \u00f6nce \u0130stanbul\u2019da k\u00fc\u00e7\u00fck bir y\u00fczdede a\u00e7\u0131p, sonra Frankfurt ve Virginia\u2019ya yayacaks\u0131n\u0131z. D\u0131\u015f d\u00fcnyaya co\u011frafi + a\u011f\u0131rl\u0131kl\u0131 bir politika, i\u00e7 d\u00fcnyaya ise split\u2011horizon ile \u00f6zel IP\u2019ler. B\u00f6yle bir kurgu, beklenmedik durumlarda geri d\u00f6n\u00fc\u015f\u00fc de kolayla\u015ft\u0131r\u0131r. \u0130\u00e7eride bir sorun oldu mu, i\u00e7 DNS d\u0131\u015far\u0131dan ba\u011f\u0131ms\u0131z ayakta durur. D\u0131\u015f d\u00fcnyada bir b\u00f6lge d\u00fc\u015fse, di\u011fer b\u00f6lgeler nazik\u00e7e y\u00fck\u00fc al\u0131r.<\/p>\n<h3><span id=\"TTL_taktigi_ve_kucuk_ritueller\">TTL takti\u011fi ve k\u00fc\u00e7\u00fck rit\u00fceller<\/span><\/h3>\n<p>Ge\u00e7i\u015f g\u00fcnlerinde TTL\u2019i biraz k\u0131sa tutup (\u00f6rne\u011fin dakikalar seviyesinde), i\u015fler yerine oturunca makul bir seviyeye geri almak iyi gidiyor. S\u0131k yap\u0131lan bir hata, ge\u00e7i\u015f bitti\u011fi halde TTL\u2019i d\u00fc\u015f\u00fck b\u0131rakmak. Gereksiz sorgu, gereksiz maliyet, b\u0131\u00e7ak s\u0131rt\u0131 de\u011fi\u015fiklik. K\u00fc\u00e7\u00fck bir al\u0131\u015fkanl\u0131k edinin: de\u011fi\u015fiklik \u00f6ncesi ve sonras\u0131 not al\u0131n, bir hafta sonra geri d\u00f6n\u00fcp TTL\u2019i g\u00f6zden ge\u00e7irin. Bu kadar basit.<\/p>\n<h3><span id=\"IPv6yi_unutmamak\">IPv6\u2019y\u0131 unutmamak<\/span><\/h3>\n<p>Bug\u00fcn trafi\u011fin ciddi bir k\u0131sm\u0131 IPv6 ile ak\u0131yor. AAAA kay\u0131tlar\u0131n\u0131 eksik ge\u00e7ince garip sorunlar ya\u015fanabiliyor. Ge\u00e7enlerde minik bir <a href=\"https:\/\/www.dchost.com\/blog\/kucuk-bir-aaaa-kaydi-buyuk-bir-aydinlanma\/\">AAAA kayd\u0131yla ilgili k\u00fc\u00e7\u00fck ama ayd\u0131nlat\u0131c\u0131 bir hikaye<\/a> payla\u015fm\u0131\u015ft\u0131m; orada da g\u00f6rd\u00fc\u011f\u00fcm gibi, tek bir eksik kay\u0131t koca zinciri etkileyebiliyor. Hatta altyap\u0131n\u0131z IPv6\u2011only bir b\u00f6lgede ise, <a href=\"https:\/\/www.dchost.com\/blog\/ipv6%e2%80%91only-vps-uzerinde-web-sitesi-yayinlamak-nat64-dns64-ile-ipv4e-nasil-kopru-kurulur\/\">IPv6\u2011only bir sunucu \u00fczerinde NAT64\/DNS64 k\u00f6pr\u00fcs\u00fc kurma<\/a> ad\u0131mlar\u0131 i\u015finizi kolayla\u015ft\u0131r\u0131r. DNS taraf\u0131nda bunun kar\u015f\u0131l\u0131\u011f\u0131, A ve AAAA kay\u0131tlar\u0131n\u0131 tutarl\u0131 y\u00f6netmek ve testleri her iki protokolde ayr\u0131 ayr\u0131 yapmak.<\/p>\n<h3><span id=\"Uygulama_katmanini_da_dusunmek\">Uygulama katman\u0131n\u0131 da d\u00fc\u015f\u00fcnmek<\/span><\/h3>\n<p>DNS i\u015finizi yapsa bile, ta\u015f\u0131d\u0131\u011f\u0131n\u0131z trafi\u011fin \u00fcst katmanda iyi kar\u015f\u0131lanmas\u0131 gerekiyor. TLS, HTTP\/2\/3, gzip\/brotli gibi detaylar kullan\u0131c\u0131 deneyimini bariz etkiliyor. Cloudflare \u00fczerinden son ad\u0131m\u0131 da g\u00fczelle\u015ftirmek i\u00e7in, <a href=\"https:\/\/www.dchost.com\/blog\/nginx-ve-cloudflareda-http-2-ve-http-3-quic-nasil-etkinlestirilir-wordpress-icin-uctan-uca-kurulum-ve-test-rehberi\/\">HTTP\/2 ve HTTP\/3\u2019\u00fc u\u00e7tan uca etkinle\u015ftirme rehberimizi<\/a> el alt\u0131nda tutmak ho\u015f olur. O yaz\u0131da, tarafa g\u00f6re nas\u0131l test edildi\u011fini ve ufak tuzaklar\u0131 da anlatm\u0131\u015ft\u0131m.<\/p>\n<h2 id=\"section-7\"><span id=\"Test_Gozlem_ve_Sorun_Giderme_Nerede_Ne_Olduyu_Sakince_Bulmak\">Test, G\u00f6zlem ve Sorun Giderme: \u201cNerede Ne Oldu?\u201dyu Sakince Bulmak<\/span><\/h2>\n<h3><span id=\"Tek_bir_aracla_degil_birkac_pencereden_bakmak\">Tek bir ara\u00e7la de\u011fil, birka\u00e7 pencereden bakmak<\/span><\/h3>\n<p>Bir kayd\u0131 g\u00fcncellediniz ve \u201cneden h\u00e2l\u00e2 eskisi geliyor?\u201d diye soruyorsunuz. Burada \u00fc\u00e7 ad\u0131ml\u0131k bir rutin \u00e7ok i\u015f g\u00f6r\u00fcyor: \u00f6nce TTL\u2019in ge\u00e7mesini beklemek, sonra farkl\u0131 resolver\u2019lardan testi tekrarlamak, en sonda da uygulama loglar\u0131na bakmak. Bazen kay\u0131t do\u011fru d\u00f6n\u00fcyor, ama CDN \u00f6nbelle\u011fi sizi eski i\u00e7eri\u011fe ba\u011fl\u0131 tutuyor. Bazen CDN tertemiz, ama uygulama taraf\u0131nda rota yanl\u0131\u015f. Bunu ay\u0131rt etmek i\u00e7in basit\u00e7e \u201cDNS ne diyor?\u201d, \u201cHTTP ba\u015fl\u0131\u011f\u0131 ne diyor?\u201d, \u201cuygulama logu ne diyor?\u201d \u00fc\u00e7l\u00fcs\u00fcn\u00fc art arda kontrol edin.<\/p>\n<h3><span id=\"Dokumantasyonlar_ve_sakin_aksam_okumalari\">Dok\u00fcmantasyonlar ve sakin ak\u015fam okumalar\u0131<\/span><\/h3>\n<p>Kavramlar\u0131n isimleri bazen kafay\u0131 kar\u0131\u015ft\u0131rabiliyor. \u201cGeolocation m\u0131, geoproximity mi?\u201d diye sorarken, k\u00fc\u00e7\u00fck bir referansa bakmak iyi geliyor. Cloudflare\u2019\u0131n resmi dok\u00fcmanlar\u0131ndaki <a href=\"https:\/\/developers.cloudflare.com\/load-balancing\/understand\/steering-methods\/geo-steering\/\" rel=\"nofollow noopener\" target=\"_blank\">geo steering b\u00f6l\u00fcm\u00fc<\/a> ve AWS\u2019nin <a href=\"https:\/\/docs.aws.amazon.com\/Route53\/latest\/DeveloperGuide\/routing-policy.html\" rel=\"nofollow noopener\" target=\"_blank\">Route 53 y\u00f6nlendirme politikalar\u0131<\/a> \u00f6zet ve nokta at\u0131\u015f\u0131. Split\u2011horizon yakla\u015f\u0131m\u0131n\u0131n tarihsel ba\u011flam\u0131n\u0131 merak ediyorsan\u0131z, <a href=\"https:\/\/en.wikipedia.org\/wiki\/Split-horizon_DNS\" rel=\"nofollow noopener\" target=\"_blank\">split\u2011horizon DNS \u00fczerine k\u0131sa notlar<\/a> da merak\u0131 tatl\u0131 tatl\u0131 gideriyor.<\/p>\n<h2 id=\"section-8\"><span id=\"Kucuk_Tuzaklar_ve_Nazik_Cozumler\">K\u00fc\u00e7\u00fck Tuzaklar ve Nazik \u00c7\u00f6z\u00fcmler<\/span><\/h2>\n<h3><span id=\"Negatif_onbellek_ve_yok_cevabi\">Negatif \u00f6nbellek ve \u201cyok\u201d cevab\u0131<\/span><\/h3>\n<p>DNS\u2019te \u201cb\u00f6yle bir kay\u0131t yok\u201d cevab\u0131 bile \u00f6nbelle\u011fe al\u0131nabiliyor. Yanl\u0131\u015fl\u0131kla bir kayd\u0131 silip geri ekledi\u011finizde, baz\u0131 kullan\u0131c\u0131lar bir s\u00fcre \u201cyok\u201d cevab\u0131n\u0131 almaya devam eder. Bu y\u00fczden kritik kay\u0131tlar\u0131 silmek yerine, m\u00fcmk\u00fcnse hedefini de\u011fi\u015ftirin. Silmek \u015fartsa, yedek bir kay\u0131t ad\u0131yla ge\u00e7ici k\u00f6pr\u00fc kurmak bazen daha g\u00fcvenli.<\/p>\n<h3><span id=\"Isimlendirme_ve_okunabilirlik\">\u0130simlendirme ve okunabilirlik<\/span><\/h3>\n<p>Topoloji b\u00fcy\u00fcd\u00fck\u00e7e kay\u0131t adlar\u0131 kabar\u0131p gidiyor. \u201capp\u2011eu\u2011blue.example.com\u201d, \u201capp\u2011eu\u2011green.example.com\u201d gibi u\u00e7lar, a\u011f\u0131rl\u0131kl\u0131 DNS\u2019te hayat kurtar\u0131yor. Hedefin ne oldu\u011funu okur okumaz anlamak, gece yar\u0131s\u0131 hatay\u0131 daha h\u0131zl\u0131 ay\u0131klat\u0131r. \u0130ki basit kural iyi gidiyor: anlaml\u0131 adlar ve k\u0131sa, tekrar edilebilir rit\u00fceller. Da\u011f\u0131t\u0131m \u00f6ncesi bir kontrol listesi, da\u011f\u0131t\u0131m sonras\u0131 k\u0131sa bir g\u00f6zden ge\u00e7irme.<\/p>\n<h3><span id=\"Once_temel_taslar\">\u00d6nce temel ta\u015flar<\/span><\/h3>\n<p>DNS\u2019in \u00fczerinde u\u00e7u\u015fan t\u00fcm bu ak\u0131l oyunlar\u0131n\u0131n sa\u011fl\u0131kl\u0131 olmas\u0131 i\u00e7in temel ta\u015flar\u0131 sa\u011flam koymak \u00f6nemli. \u00d6zellikle kendi alan ad\u0131n\u0131z\u0131n otoritatif isim sunucular\u0131na karar verirken, yap\u0131 ta\u015flar\u0131ndan emin olun. \u0130lk kez kuranlar i\u00e7in, <a href=\"https:\/\/www.dchost.com\/blog\/ozel-ad-sunucusu-ve-glue-record-nasil-kurulur-kendi-dnsine-adim-adim-yolculuk\/\">\u00f6zel ad sunucusu ve glue record kurulumunu<\/a> ad\u0131m ad\u0131m g\u00f6rmek g\u00fcven veriyor. Bu par\u00e7a d\u00fczg\u00fcnse, gerisi daha kolay ak\u0131yor.<\/p>\n<h2 id=\"section-9\"><span id=\"Kapanis_Yumusak_Gecislerin_ve_Dogru_Adreslerin_Mutlulugu\">Kapan\u0131\u015f: Yumu\u015fak Ge\u00e7i\u015flerin ve Do\u011fru Adreslerin Mutlulu\u011fu<\/span><\/h2>\n<p>\u015eunu fark ettim: DNS taraf\u0131nda k\u00fc\u00e7\u00fck, sakin bir dokunu\u015f \u00e7o\u011fu zaman uygulama taraf\u0131ndaki b\u00fcy\u00fck de\u011fi\u015fikliklerden daha etkili olabiliyor. <strong>Co\u011frafi y\u00f6nlendirme<\/strong> ile kullan\u0131c\u0131y\u0131 yak\u0131n hissettirmek, <strong>a\u011f\u0131rl\u0131kl\u0131 DNS<\/strong> ile ge\u00e7i\u015fleri yormadan yapmak, <strong>split\u2011horizon<\/strong> ile i\u00e7erisi\u2011d\u0131\u015far\u0131s\u0131 dengesini kurmak. Hepsi kendi ba\u015f\u0131na anlaml\u0131, birlikteyse \u015fahane. Kar\u015f\u0131l\u0131\u011f\u0131nda da daha mutlu kullan\u0131c\u0131lar, daha sakin gece n\u00f6betleri.<\/p>\n<p>Pratik tavsiye olarak, ge\u00e7i\u015f g\u00fcnlerinde TTL\u2019i nazik\u00e7e k\u0131salt\u0131n, farkl\u0131 resolver\u2019lardan test etmeyi al\u0131\u015fkanl\u0131k haline getirin, bak\u0131m \u00f6ncesi k\u00fc\u00e7\u00fck bir geri d\u00f6n\u00fc\u015f plan\u0131n\u0131 kenarda tutun. Co\u011frafi kurgularda k\u00fc\u00e7\u00fck istisnalar i\u00e7in bir ka\u00e7\u0131\u015f rotas\u0131 b\u0131rak\u0131n, weighted senaryolarda da \u00f6l\u00e7\u00fcm\u00fc tek kaynaktan de\u011fil farkl\u0131 pencerelerden yap\u0131n. Umar\u0131m bu yolculuk, kendi sisteminizde bir iki ta\u015f\u0131 yerine oturtur. Sorularla, notlarla, akl\u0131n\u0131za tak\u0131lanlarla yine bulu\u015furuz. Bir dahaki yaz\u0131da g\u00f6r\u00fc\u015fmek \u00fczere.<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>\u0130&ccedil;indekiler1 Ofiste Ba\u015flayan K\u00fc\u00e7\u00fck Bir DNS Maceras\u01312 DNS\u2019in Sahne Arkas\u0131: Neden Bazen Bekledi\u011finizi Alamazs\u0131n\u0131z?2.1 Resolver\u2019lar, TTL\u2019ler ve o me\u015fhur \u00f6nbellek2.2 Y\u00fczdeler neden birebir kullan\u0131c\u0131ya yans\u0131maz?3 Co\u011frafi DNS: \u201cNereden Geliyorsun?\u201d Sorusu ve Nazik Y\u00f6nlendirme3.1 \u00dclke, b\u00f6lge, \u015fehir\u2026 Ne kadar ince ayar?3.2 EDNS ipucu ve test ederken dikkat4 A\u011f\u0131rl\u0131kl\u0131 (Weighted) DNS: Trafi\u011fi Yumu\u015fac\u0131k B\u00f6lmenin En Tatl\u0131 Yolu4.1 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1505,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-1504","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-teknoloji"],"_links":{"self":[{"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/posts\/1504","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/comments?post=1504"}],"version-history":[{"count":0,"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/posts\/1504\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/media\/1505"}],"wp:attachment":[{"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/media?parent=1504"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/categories?post=1504"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.dchost.com\/blog\/wp-json\/wp\/v2\/tags?post=1504"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}