Iyini i-DNS?
Ngaso sonke isikhathi uma uvula iwebhusayithi, insizakalo yohla lwemibhalo engabonakali ihumusha igama olithayiphile inombolo engafinyelelwa yikhompyutha yakho. Nansi indlela i-Domain Name System isebenza ngayo - nokuthi ungafunda kanjani lokho ekushicilela nganoma yisiphi isizinda.
Incwadi yocingo ye-inthanethi
Amakhompyutha awaphequluli ngamagama — axhuma ku Amakheli e-IP. I-DNS, i Uhlelo Lwegama Lesizinda, uhla lwemibhalo olusabalalisiwe olubonisa amagama akhumbulekayo njenge example.com kulezo zinombolo. Yasungulwa ngo-1983 ngokuqondile ngoba ifayela lokuqala le-intanethi elibanjwe e-Stanford lalingakwazi ukuligcina.
Izinto ezimbili ezenza i-DNS iphawuleke: kunjalo kwabiwa (awukho umshini owodwa owazi konke), futhi kunjalo kugcinwe yonke indawo (izimpendulo zikhunjulwa isikhashana, ngakho ukubheka kuyashesha). Zombili izakhiwo zilolonga indlela isistimu eziphatha ngayo usuku nosuku.
Kwenzekani ngesikhathi sokubheka i-DNS
Uma isiphequluli sakho sikucela iwebhusayithi, uchungechunge lwamaseva e-DNS lusebenzisana ngama-millisecond ambalwa:
# 1. Idivayisi yakho ibuza isixazululi sayo esimisiwe (ngokuvamile ama-ISP akho, noma 8.8.8.8 / 1.1.1.1) # 2. Isixazululi, uma singenayo impendulo egcinwe kunqolobane, sihamba ngohlelo: # amaseva ezimpande → ".com" amaseva → amaseva egama elithi example.com # 3. Iseva egunyaziwe yesizinda iphendula ngamarekhodi angempela # 4. Isixazululi sigcina impendulo ye-TTL yerekhodi bese sikuphendula
I-hop yokugcina - iseva enkulumela isizinda ngokwaso - yilokho amarekhodi e-NS (ngezansi) akhomba kukho. Konke okungenhla kuwukuthuma nje.
Izinhlobo zamarekhodi ezibalulekile
Indawo ye-DNS yesizinda iyisizindalwazi esincane samarekhodi athayiphiwe. Nawa ozohlangana nawo ngempela:
| Uhlobo | Ekwenzayo | Isibonelo |
|---|---|---|
| A | Imepha igama ekhelini le-IPv4 | example.com → 93.184.216.34 |
| AAAA | Imepha igama ekhelini le-IPv6 | example.com → 2606:2800::2201 |
| CNAME | Isibizo: ukhomba igama kwelinye igama | www.example.com → example.com |
| MX | Amaseva e-imeyili athola i-imeyili yesizinda | 10 aspmx.l.google.com |
| TXT | Umbhalo wamahhala: I-SPF anti-spam, i-DKIM, ubufakazi bobunikazi | "v=spf1 -all" |
| NS | Amaseva egama agunyaziwe wezoni | ns1.examplehost.com |
| CAA | Yiziphi iziphathimandla zesitifiketi ezingakhipha izitifiketi ze-TLS | 0 issue "letsencrypt.org" |
| SOA | Imethadatha yendawo: iseva eyinhloko, othintana naye, izibali-sikhathi zokulondoloza isikhashana | ns1. dns-admin. … |
| PTR | Okuhlanekezelwe: imephu ibuyisela i-IP egameni lomethuleli | 8.8.8.8 → dns.google |
Okubi okubili okufanele ukwazi: i-CNAME injalo akuvunyelwe empandeni yesizinda (yingakho example.com isebenzisa amarekhodi e-A/AAAA ngokuqondile), kanye nesizinda esina MX "0 ." unayo a null MX — indlela yangamabomu yokuthi "lesi sizinda sithumela i-imeyili kodwa asiyitholi".
Ukulondoloza isikhashana, i-TTL nokusabalalisa
Wonke amarekhodi ane-a I-TTL (isikhathi sokuphila) - inani lamasekhondi abaxazululi bangaphinda basebenzise impendulo ngaphambi kokubuza futhi. I-TTL yamasekhondi angu-3600 isho kufika ehoreni lokugcinwa kwesikhashana emhlabeni wonke; i-TTL yamasekhondi angu-60 isho ukuthi izinguquko zivela ngaphansi komzuzu.
Yilokhu abantu abakushoyo ngokuthi "ukusakazwa kwe-DNS": akukho ukusakazwa kwezinguquko, izinqolobane nje ziphelelwa yisikhathi ngesivinini sazo. Ngaphambi kokufuduka okuhleliwe, iqhinga lakudala ukwehlisa i-TTL kusenesikhathi, wenze iswishi, uyibuke ihlale yonke indawo ngokushesha, bese uphakamisa i-TTL futhi ukuze ujabulele ukugcinwa kwesikhashana.
Ithiphu yokuxazulula inkinga: uma isayithi lilayishela abanye kodwa hhayi wena, isixazululi sakho sendawo singase sibambe impendulo endala egcinwe kunqolobane. Ukushintshela idivayisi yakho ku-1.1.1.1 noma ukusula inqolobane ye-DNS ngokuvamile kuyayixazulula.
Hlola i-DNS yanoma iyiphi isizinda ngokwakho
Awuwadingi amathuluzi omugqa womyalo - izinsiza zesiphequluli zethu zibuza izixazululi ze-Google ne-Cloudflare bukhoma:
- Isihloli se-DNS - donsa lonke uhlobo lwerekhodi lanoma yisiphi isizinda ngokuchofoza okukodwa.
- Isizinda kuya ku-IP - bona amakheli isizinda esikhomba kuwo, nemininingwane yokubamba.
- Hlehlisa ukubheka kwe-IP - Irekhodi le-PTR: okuyigama lomethuleli izimpendulo ze-IP kulo.
Funda kabanzi
- Ingabe ufuna ukwazi izinombolo ngakolunye uhlangothi? Funda ukuthi liyini ikheli le-IP noma i IPv4 vs IPv6 ukuqhathanisa.
- Ukuphenya isithunzi se-IP? Bona i- Umhlahlandlela wohlu lwabavinjelwe we-IP.
Imibuzo ye-DNS
Iyini i-DNS ngamagama alula?
I-DNS (Isistimu Yegama Lesizinda) iyincwadi yocingo ye-inthanethi: ihumusha amagama ongawabhala, njenge-example.com, kumakheli e-IP amakhompyutha axhumeka kuwo. Ngaphandle kwayo, kuzodingeka ubambe ngekhanda amakheli ezinombolo kuwo wonke amawebhusayithi.
Athini amakheli 8.8.8.8 kanye 1.1.1.1?
Izixazululi ze-DNS ezisesidlangalaleni eziqhutshwa i-Google ne-Cloudflare. I-ISP yakho isebenzisa eyodwa ngokuzenzakalelayo, kodwa noma ubani angabuza lezi ezisesidlangalaleni esikhundleni salokho - zimahhala, ziyashesha futhi ngokuvamile ziyashesha ukuthola izinguquko ze-DNS. Amathuluzi ethu e-DNS abuza womabili phezu kwe-DNS-over-HTTPS ebethelwe.
Ushintsho lwe-DNS luthatha isikhathi esingakanani ukusebenza yonke indawo?
Inqobo nje uma i-TTL yerekhodi yangaphambilini (isikhathi sokuphila). Izimpendulo zenqolobane yezixazululi zesikhathi se-TTL — imizuzwana kuya ezinsukwini — ngakho ngemva kokuhlela irekhodi, izixazululi emhlabeni wonke ziqhubeka nokunikeza impendulo endala kuze kube yilapho ikhophi yazo egcinwe kunqolobane iphelelwa yisikhathi. Yehlisa i-TTL ngaphambi koshintsho oluhleliwe ukuze wenze ukushintsha kusheshe.
Uyini umehluko phakathi kwe-DNS nekheli le-IP?
Ikheli le-IP inombolo ekhomba idivayisi eku-inthanethi; I-DNS isistimu eyenza amagama esizinda akhumbuleke kulezo zinombolo. Isizinda igama, i-IP indawo okuyiwa kuyo, futhi i-DNS iwukuhumusha phakathi kwazo.