A network administrator is troubleshooting a connection failure where internal application servers reject connections from newly deployed management systems. Log analysis reveals that the application servers perform a mandatory reverse IP lookup to validate host identity before establishing a session. While forward lookup zones resolve hostnames to IP addresses correctly, reverse lookups fail for statically addressed hosts because Dynamic DNS (DDNS) updates are only executed by dynamic DHCP clients. Which DNS record type must be manually created in the reverse lookup zone to resolve this issue?
- PTR records mapping the IP addresses of the static management systems to their canonical hostnamesCevap
- BCNAME records pointing the static IP addresses to the existing forward A records of the hosts
- CDHCP Relay IP Helper addresses configured on the local switch interfaces to relay dynamic updates
- DSRV records defining the service ports and transport protocols used by DNS name resolution daemons
Cevap
Manually creating Pointer (PTR) records in the reverse lookup zone resolves IP addresses to domain names for static hosts.
Reverse DNS lookups query the reverse lookup zone (in-addr.arpa for IPv4) to convert an IP address into a domain name. Because statically configured hosts do not automatically register reverse records via DHCP/DDNS integration, PTR (Pointer) records must be manually created to populate the reverse lookup zone and satisfy security authentication checks.
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Anahtar Kavram
DNS Record Types and Reverse Lookup Operation