Search results
Results from the WOW.Com Content Network
Additionally, the answer returned is also allowed to be cached by recursive DNS servers. This is especially helpful because a second lookup for the same address performed by the same node would probably be answered from the local cache instead of querying the authoritative servers again. This helps reduce the network load significantly.
A URI DNSBL query (and an RHSBL query) is fairly straightforward. The domain name to query is prepended to the DNS list host as follows: example.net.dnslist.example.com where dnslist.example.com is the DNS list host and example.net is the queried domain. Generally if an A record is returned the name is listed.
For example, to do a reverse lookup of the IP address 8.8.4.4 the PTR record for the domain name 4.4.8.8.in-addr.arpa would be looked up, and found to point to dns.google. If the A record for dns.google in turn pointed back to 8.8.4.4 then it would be said to be forward-confirmed.
dig is a network administration command-line tool for querying the Domain Name System (DNS). dig is useful for network troubleshooting and for educational purposes. [2] It can operate based on command line option and flag arguments, or in batch mode by reading requests from an operating system file.
nslookup operates in interactive or non-interactive mode. When used interactively by invoking it without arguments or when the first argument is - (minus sign) and the second argument is a hostname or Internet address of a name server, the user issues parameter configurations or requests when presented with the nslookup prompt (>).
Like the CNAME record, the DNS lookup will continue by retrying the lookup with the new name. The name server synthesizes a CNAME record to actually apply the DNAME record to the requested name—CNAMEs for every node on a subtree have the same effect as a DNAME for the entire subtree. For example, if there is a DNS zone as follows:
A public recursive name server (also called public DNS resolver) is a name server service that networked computers may use to query the Domain Name System (DNS), the decentralized Internet naming system, in place of (or in addition to) name servers operated by the local Internet service provider (ISP) to which the devices are connected. Reasons ...
ttl: standard DNS time to live field. IN: standard DNS class field (this is always IN). SRV: Type of Record (this is always SRV). priority: the priority of the target host, lower value means more preferred. weight: A relative weight for records with the same priority, higher value means higher chance of getting picked.