Menene DNS?
DNS (Domain Name System) shine littafin tarho na intanet. Yana canza sunayen yanki da mutane ke iya karantawa (misali, example.com) zuwa adiresoshin IP da kwamfutoci suke fahimta. Bayanan DNS kuma suna ƙayyade ƙa'idojin wannan tsarin canzawa.
Bayanan A
Bayanan A (Address) yana nuna sunan yanki zuwa adireshin IPv4. Wannan shine mafi asalin nau'in bayanan DNS:
example.com. IN A 93.184.216.34Kowace shafin yanar gizo tana buƙatar aƙalla bayanan A ɗaya.
Bayanan AAAA
Bayanan AAAA shine sigar IPv6 na bayanan A. Adiresoshin IPv6 sun fi tsawo kuma suna ba da ƙarin sararin adiresoshi:
example.com. IN AAAA 2606:2800:220:1:248:1893:25c8:1946Bayanan MX
Bayanan MX (Mail Exchange) yana ƙayyade wane server zai karɓi imel ɗin da aka aiko zuwa yankin ku. Ana saita shi tare da darajar fifiko — ƙaramin lamba yana nufin fifiko mafi girma:
example.com. IN MX 10 mail.evilmail.com.
example.com. IN MX 20 mail2.evilmail.com.Bayanan CNAME
Bayanan CNAME (Canonical Name) yana nuna sunan yanki ɗaya zuwa wani. Yana aiki kamar sunan laƙabi:
www.example.com. IN CNAME example.com.Ba za a iya amfani da bayanan CNAME don tushen yanki ba — kawai don ƙananan yankuna.
Bayanan TXT
Bayanan TXT yana adana kowane irin rubutun bayanai. Yawancin lokaci ana amfani da shi don ka'idojin tabbatar da imel kamar SPF, DKIM, da DMARC:
example.com. IN TXT "v=spf1 include:evilmail.com ~all"Bayanan NS
Bayanan NS (Name Server) yana nuna wane server ke sarrafa DNS na yankin:
example.com. IN NS ns1.evilmail.com.
example.com. IN NS ns2.evilmail.com.Bayanan SRV
Bayanan SRV (Service) yana ƙayyade wurin sabis na musamman. Tsarin: fifiko, nauyi, tashar, da manufa:
_imap._tcp.example.com. IN SRV 0 1 993 imap.evilmail.com.Bayanan CAA
Bayanan CAA (Certification Authority Authorization) yana ƙayyade wane hukumomin takaddun shaida za su iya ba da takardar SSL/TLS don yankin ku:
example.com. IN CAA 0 issue "letsencrypt.org"TTL: Tsawon rayuwa
TTL (Time to Live) yana ƙayyade tsawon lokacin da za a adana bayanan DNS a cikin rumbun ajiya a cikin dakiku. Ƙaramin TTL (300 dakiku) yana nufin sabuntawa mafi sauri, amma yana haifar da ƙarin buƙatun DNS. Babban TTL (86400 dakiku — rana 1) yana nufin ƙarancin buƙatoci, amma canje-canje suna yaɗuwa a hankali.
Gyara matsalolin DNS
Don bincika matsalolin DNS, ku yi amfani da waɗannan umarni:
# Bincika bayanan A
dig A example.com
# Bincika bayanan MX
dig MX example.com
# Bincika duk bayanai
dig ANY example.com
# Neman daga wani server na DNS na musamman
dig @8.8.8.8 example.com
# Bincika yaɗuwar DNS
nslookup example.comWaɗannan umarni suna taimaka wajen tabbatar da daidaiton saitunan DNS ɗinku da gano matsaloli.