{"id":654,"date":"2015-12-04T07:25:24","date_gmt":"2015-12-04T04:25:24","guid":{"rendered":"http:\/\/www.linux-destek.com\/?p=654"},"modified":"2015-12-04T07:25:24","modified_gmt":"2015-12-04T04:25:24","slug":"postfix-ndr-spam-backscatter-engelleme","status":"publish","type":"post","link":"https:\/\/www.48k.com.tr\/postfix-ndr-spam-backscatter-engelleme\/","title":{"rendered":"Postfix NDR spam backscatter engelleme"},"content":{"rendered":"

\"emailbackscatter\"<\/a>Backscatter Nedir?<\/h3>\n

Her SMTP sunucusu al\u0131c\u0131s\u0131na iletemedi\u011fi epostalar\u0131 (bounce ) bir ba\u015fka bildirimle g\u00f6ndericiye iletmek zorundad\u0131r.Bu bir standartt\u0131r.G\u00f6nderici g\u00f6nderdi\u011fi epostay\u0131 al\u0131c\u0131s\u0131na ula\u015fmad\u0131\u011f\u0131n\u0131 bu bildirim mesaj\u0131yla farkeder.Bu bildirimin ad\u0131 non delivery reports veya k\u0131sa ndr,di\u011fer ba\u015fka bir tan\u0131m\u0131 da DSN yani Delivery Status Notification ‘dur.<\/p>\n

Bu tasarlanan,iyiye hizmet eden bili\u015fimin eskide kalm\u0131\u015f bir hikayesi.Ger\u00e7ek d\u00fcnyada ise durum \u015f\u00f6yle;<\/p>\n

Bu raporlama sisteminin k\u00f6t\u00fc ama\u00e7la kullan\u0131labilece\u011fini farkeden a\u015f\u0131r\u0131 zeki spamc\u0131 milleti \u00e7akt\u0131rmadan\u00a0 milyonlarca spam g\u00f6nderebilmekte.Nas\u0131l m\u0131?<\/p>\n

Bilindi\u011fi gibi epostada bir envelope sender ayn\u0131 zamanda authenticated sender olmak zorunda de\u011fil.Yani eski mektup g\u00f6nderdi\u011fimiz g\u00fcnlere d\u00f6necek olursak.G\u00f6nderece\u011fim zarf\u0131n \u00fczerine kendi ad\u0131m\u0131 yazmak zorunlulu\u011fum yok.<\/p>\n

Backscatter epostan\u0131n envelope sender b\u00f6l\u00fcm\u00fcne istenilen email adresini yaz\u0131l\u0131r.Al\u0131c\u0131 k\u0131sm\u0131nda da kar\u015f\u0131 tarafta bulunmayan bir eposta adresi belirtildi\u011finde g\u00f6nderilen epostay\u0131\u00a0 al\u0131c\u0131 smtp sunucusu red edecektir.Peki bu durumda NDR nereye g\u00f6nderilecek?Elbette envelope sender k\u0131sm\u0131ndaki kurban\u0131m\u0131z\u0131n eposta adresine.Karda y\u00fcr\u00fc ama izini belli etme.<\/p>\n

\u00c7\u00f6z\u00fcm<\/h3>\n

San\u0131yorum ki binlerce dolar \u00f6denen o pek g\u00f6zde,pek g\u00fczide eposta sistemleri kendi i\u00e7inde bir mekanizmayla bu i\u015fi \u00e7\u00f6zm\u00fc\u015flerdir.<\/p>\n

Ama binlerce dolar\u0131m yok,ayn\u0131 zamanda hosting i\u015findeyim diyorsan\u0131z hayat size biraz daha zor.Zira elimizde kullanabildi\u011fimiz en modern,geli\u015fmi\u015f ve g\u00fcvenli smtp postfix.Postfixin resmi sayfas\u0131nda backscatter engelleme ile ilgili bir tak\u0131m \u00e7\u00f6z\u00fcm \u00f6nerileri var.Tembellik etmedim okudum.Neticede sunucunuzda bir veya birka\u00e7 hosting ko\u015fuyorsa kabul edilebilir bir \u00e7\u00f6z\u00fcm sunulmu\u015f.Ancak bu \u00e7\u00f6z\u00fcm,payla\u015f\u0131ml\u0131 bir hosting sunucusu y\u00f6netiyorsan\u0131z ve \u015f\u00f6yle 50-100 ve \u00fczeri hosting bar\u0131nd\u0131r\u0131l\u0131yorsa hi\u00e7bir i\u015fe yaramaz.<\/p>\n

Yine ger\u00e7ek d\u00fcnyadan bir \u00f6rnek vermek gerekirse;zaten yukarda s\u00f6z\u00fcn\u00fc etti\u011fimiz raporlama sistemi kan\u0131mca pek bir i\u015fe yaram\u0131yor.\u00c7\u00fcnk\u00fc kimse pc ba\u015f\u0131nda kar\u015f\u0131s\u0131na \u00e7\u0131kan hata mesajlar\u0131n\u0131 okumuyor.O y\u00fczden k\u00f6kten \u00e7\u00f6z\u00fcm olarak\u00a0 NDR’\u0131 komple kapatma yolunu se\u00e7ebilirsiniz.<\/p>\n

Bunun i\u00e7in postfix’in master.cf dosyas\u0131n\u0131 a\u00e7\u0131n.<\/p>\n

ve a\u015fa\u011f\u0131daki sat\u0131r\u0131;<\/p>\n

bounce\u00a0\u00a0\u00a0 unix\u00a0 –\u00a0\u00a0 \u00a0–\u00a0\u00a0 \u00a0n\u00a0\u00a0 \u00a0–\u00a0\u00a0 \u00a00\u00a0\u00a0\u00a0 bounce<\/p>\n

\u015fu \u015fekilde de\u011fi\u015ftirin;<\/p>\n

bounce\u00a0\u00a0\u00a0 unix\u00a0 –\u00a0\u00a0 \u00a0–\u00a0\u00a0 \u00a0n\u00a0\u00a0 \u00a0–\u00a0\u00a0 \u00a00\u00a0\u00a0 \u00a0discard<\/p>\n

dosyay\u0131 kaydedip kapatt\u0131ktan sonra postfix servisini restart edin.Hepsi bu kadar.<\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

Backscatter Nedir? Her SMTP sunucusu al\u0131c\u0131s\u0131na iletemedi\u011fi epostalar\u0131 (bounce ) bir ba\u015fka bildirimle g\u00f6ndericiye iletmek zorundad\u0131r.Bu bir standartt\u0131r.G\u00f6nderici g\u00f6nderdi\u011fi epostay\u0131 al\u0131c\u0131s\u0131na ula\u015fmad\u0131\u011f\u0131n\u0131 bu bildirim mesaj\u0131yla farkeder.Bu bildirimin ad\u0131 non delivery reports veya k\u0131sa ndr,di\u011fer ba\u015fka bir tan\u0131m\u0131 da DSN yani Delivery Status Notification ‘dur. Bu tasarlanan,iyiye hizmet eden bili\u015fimin eskide kalm\u0131\u015f bir hikayesi.Ger\u00e7ek d\u00fcnyada ise […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[312,291],"tags":[525,526,527,313,528,287,529,530,327,329],"class_list":["post-654","post","type-post","status-publish","format-standard","hentry","category-e-mail-sunuculari","category-uncategorized-tr","tag-backscatter","tag-bounce-spam","tag-dsn","tag-email","tag-eposta","tag-linux","tag-ndr","tag-ndr-spam-engelleme","tag-postfix","tag-spam"],"_links":{"self":[{"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/posts\/654"}],"collection":[{"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/comments?post=654"}],"version-history":[{"count":0,"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/posts\/654\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/media?parent=654"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/categories?post=654"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.48k.com.tr\/wp-json\/wp\/v2\/tags?post=654"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}