Coyote Point Systems E350GX, Руководство по установке и администрированию

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Appendix J: Glossary
328 Equalizer Installation and Administration Guide
server cluster A group of servers that are components in a network and joined through
hardware or software. See cluster. See also FTP cluster, geographic cluster,
and virtual cluster. See server.
server draining The process of allowing existing connections to a server to complete while not
allowing any new connections, so that the server is eventually not serveing
any traffic. Usually done in preparation for shutting down, rebooting, or
upgrading a server. On Equalizer, server draining is enabled using the
quiesce server option.
server endpoint An IP address-port pair that identifies a physical or virtual server on the
internal network to which Equalizer can route connection requests. See
server.
server weight A value that indicates the relative proportion of connection requests that a
particular server will receive. See dynamic weight, server, initial weight, and
weight.
session A logical connection between a server and a client that may span a series of
individual client requests and server responses (i.e., transactions). Depending
on the application, a session may also span multiple client-server connections
as well as transactions. Session data is typically maintained using cookies
inserted into client requests and server responses, by Equalizer, servers, or
both. Session data may also be maintained on clients and servers. Equalizer
uses cookies at Layer 7 and a sticky timer at Layer 4 to provide server
persistence; the cookie lifetime or sticky time to set on Equalizer is
determined by the application, and should usually match the corresponding
cookie or session timeouts set on the real servers in a cluster.
site An Envoy site is part of an Envoy geocluster. It points to an existing virtual
cluster on an Equalizer running Envoy.
spoofing Using the client’s IP address for the source IP address in client requests. This
fools (or spoofs) the server into regarding the client as the source of the
request. For spoofing to work, the default gateway for the server must be set
to Equalizer’s internal IP address.
SSL See Secure Sockets Layer (SSL).
stack An area of reserved memory in which applications place status data and other
data. See protocol stack.
stale connection A partially open or closed connection.
state Status; the current condition of a network, computer, or peripherals.
stateless A condition in which a server processes each request from a site
independently and cannot store information about prior requests from that
site. Each request stands on its own. See also DNS and RADIUS.
sticky connection A Layer 4 connection in which a particular client remains connected to same
server to handle subsequent requests within a set period of time. Sticky
connections are managed on Equalizer using sticky records, which record the
server-client connection details; sticky records expire according to the
configured sticky timer setting.