Cov txheej txheem:
Video: Hom DNS cov ntaub ntawv yog www?
2024 Tus sau: Lynn Donovan | [email protected]. Kawg hloov kho: 2023-12-15 23:47
Cov ntaub ntawv pov thawj
| Hom | Hom id. (decimal) | Kev piav qhia |
|---|---|---|
| MX | 15 | Xa ntawv pauv sau tseg |
| NAPTR | 35 | Lub npe Authority Pointer |
| NS | 2 | Lub npe server sau tseg |
| NWS | 47 | Next Secure sau tseg |
Ib yam li ib tug yuav nug, dab tsi yog hom teb hauv DNS cov ntaub ntawv?
A Cov ntaub ntawv . A Cov ntaub ntawv yog qhov yooj yim tshaj plaws hom ntawm DNS cov ntaub ntawv thiab siv los taw qhia tus sau orsubdomain rau qhov chaw nyob IP. Muab tus nqi rau tus A sau tseg yog yooj yim li muab koj DNS tswj vaj huam sib luag nrog anIP chaw nyob rau qhov chaw sau lossis subdomain yuav tsum taw tes thiab aTTL.
Tsis tas li ntawd, muaj pes tsawg hom DNS cov ntaub ntawv muaj? 3 hom DNS queries-recursive, iterative, thiab non-recursive. 3 hom DNSservers - DNS Kev daws teeb meem, DNS Hauv paus Server thiab Lub Npe Lub Npe Server. 10 hom ntawm common DNSrecords -xws li A, AAAA, CNAME, MX thiab NS.
Yog li ntawd, dab tsi yog hom ntaub ntawv tshaj plaws hauv DNS?
Cov ntaub ntawv DNS nquag thiab lawv siv
- Cov ntaub ntawv A yog ib qho ntawm cov ntaub ntawv siv ntau tshaj plaws hauv DNS system.
- Cov ntaub ntawv MX, uas sawv cev rau "kev sib pauv xa ntawv", yog siv los txheeb xyuas cov ntawv xa ntawv uas yuav tsum xa mus rau adomain.
- NS cov ntaub ntawv txheeb xyuas qhov twg DNS server yog tso cai rau thaj chaw sib txawv.
DNS thiab hom DNS yog dab tsi?
Feem ntau hom ntawm cov ntaub ntawv khaws tseg rau hauv DNS database yog rau Start of Authority (SOA), IP chaw nyob (A thiab AAAA), SMTP mail exchangers (MX), npe servers (NS), taw tes rau thim rov qab DNS lookups (PTR), thiab domain namealiases (CNAME).
Pom zoo:
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