DNS

In the Ultra Transcenders books

AZ-305AZ-104AZ-900AI-200DP-750SC-900AB-900SC-200SC-300AZ-400AZ-802MD-102ALZ

Each book explains DNS in context, with comparison tables and the common traps.

Terms in this definition

• Chat message roles

  Labels on chat messages: instructions go under system, the person's input under user, the model's previous answers under assistant, and results returned by a called tool under tool (or function).

• 168.63.129.16

  Special platform address (WireServer) through which Azure delivers the VM agent channel, built-in DNS, DHCP and load balancer health probes. Traffic to it must stay open, or those platform functions stop working.

Related terms

• A record

  Points a DNS name at an IPv4 address. A typical use is pointing a root (apex) domain at an app.

• AAAA

  Maps a hostname to an IPv6 address in DNS; IPv4 addresses use A records.

• AAAA record

  Type of DNS entry that resolves a host to its IPv6 address.

• Active Directory-integrated zone

  A zone whose DNS data lives in Active Directory on DCs and replicates along with it, which enables secure dynamic updates and multimaster writes.

• Aging and scavenging

  Removes stale dynamically registered DNS records once both the no-refresh and refresh intervals (seven days each by default) have passed after their timestamp.

• AXFR

  Full zone transfer: a secondary DNS server receives the whole zone, whereas IXFR sends only changes.

• Azure DNS

  Family of Azure services for hosting and resolving DNS, covering public zones, private zones and DNS Private Resolver; you can't register domain names through it.

• Azure DNS Private Resolver

  Managed resolver inside a VNet that removes the need for DNS server VMs in hybrid setups. Its inbound and outbound endpoints each need their own subnet of at least /28 delegated to Microsoft.Network/dnsResolvers, and it can link only to a VNet in the same region.