Manual Chapter : 3-DNS Administrator Guide v1.0.6: Glossary

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3-DNS Controller versions 1.x - 4.x

  • 1.0.6
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Term Definition
BIG/ip Controller A Service Array Controller that monitors each server for application availability and performance, and automatically routes incoming queries to the most available server.
big3d The listener that runs on each BIG/ip Controller and responds to 3DNS Controller queries.
BIND (Berkley Internet Name Domain) The most common implementation of DNS which provides a system for matching domain names to IP addresses.
daemon A program that runs in the background on UNIX systems and responds to requests from services or from other hosts on a network.
data collector Any 3DNS Controller that collects data. Each 3DNS Controller is a data collector until you designate it a data copier with the globals sub-statement primary_ip.
data copier A 3DNS Controller that copies data from data collectors at intervals specified with the globals sub-statement sync_db_interval. Any 3DNS Controller that contains the globals sub-statement primary_ip is a data copier.
DNS (Domain Name System) A distributed database that maps IP addresses to host names.
DNS server See name server.
encryption key The sequence of data that prevents unauthorized access to other data.
fallback address See wide IP key.
FDDI (Fiber Distributed Data Interface) A multi-mode protocol for transmitting data on optical-fiber cables up to 100Mbps.
F-Secure SSH An encryption utility that allows secure shell (SSH) connections to a remote system such as the BIG/ip Controller.
gateway Hardware and/or software that forwards data between two networks.
host Any computer on a network that makes services available to other computers on the network.
host machine For the purposes of this manual, "host machine" refers to a single network server or a server array controller other than a BIG/ip Controller.
HUP A BIND name server signal. It causes the name server to reload configuration files. Use this signal after modifying the name server's boot file or one of its database files for the changes to take effect. You can also send this signal to BIND 4.93 secondary name servers to update its secondary zones.
ICMP (Internet Control Message Protocol) An Internet communications protocol. This protocol provides information relevant to IP packet processing and error correction.
INT A BIND name server signal. It saves a copy of the name server's database to a file called named_dump.db. This file is located in /var/tmp or /usr/tmp, depending on your configuration.
InterNIC A US organization that registers domain names and IP addresses and distributes information about the Internet. The InterNIC Internet address is
iQuery A UDP-based protocol used to communicate and exchange information between BIG/ip Controllers and 3DNS Controllers.
local DNS A DNS server making the name resolution request on behalf of a client. From the perspective of the 3DNS Controller, the local DNS is the source of the name resolution request.
name server A computer that can answer DNS queries. Name servers contain information about some part of the DNS, and they make that information available to clients. Also called DNS server.
named (name server daemon) The name server daemon, which manages domain name server software.
node A specific server in the array managed by a BIG/ip Controller.
path A logical route between a BIG/ip Controller and a local DNS.
pool A group of virtual servers defined and owned by BIG/ip Controllers and other host machines that are load balanced as part of a wide IP.
primary DNS The name server that manages the authoritative domain name information for a zone.
QOS (Quality of Service) A dynamic load balancing mode that bases connection distribution on a configurable combination of the packet rate, completion rate, round trip time, and topology modes.
resolution In DNS terminology, the process by which a name server retrieves data that is requested by a resolver, and sends it to the resolver.
resolvers In DNS terminology, the clients that accesses name servers. A resolver queries a name server, interprets the responses, and returns the information to the program that requested it.
resource record The building blocks of the DNS. A resource record (RR) consists of a name, a type, and data that is specific to the type. These resource records, in a hierarchical structure, make up the DNS
RTT (Round Trip Time) A calculation of the time (in microseconds) that the local DNS takes to respond to a probe issued by the big3d utility.
secondary DNS A name server that gets DNS data from the name server that is authoritative for the DNS zone.
TTL (Time to Live) A variable that controls how long information is kept in the cache and used in making decisions.
virtual address An IP address associated with one or more virtual servers managed by the BIG/ip Controller.
virtual port One component of a virtual server. The virtual port number should be the same TCP or UDP port number that is known to client programs.
virtual server A specific combination of a virtual address and virtual port, associated with a content site that is managed by a BIG/ip Controller or other host machine.
wide IP Manages and balances information on BIG/ip Controllers or other host machines by mapping a domain name to a load balancing method and a set of virtual servers.
wide IP key The wide IP key is sometimes referred to as the fallback address. The wide IP key is the same address as the domain name address (the DNS A record) and the wide IP address.
WKS (Well-Known Services) A type of resource record that describes the services usually provided by a particular protocol on a particular port.
zone files A DNS term. A database file that stores domains with one or many domain names, designated mail servers, a list of other name servers that can answer resolution requests, and a set of zone attributes called SOA (Start Of Authority).