Lenovo Flex System Fabric CN4093 User Manual

© Copyright Lenovo 2017 Chapter 37: Service Location Protocol 577
Chapter 37. Service Location Protocol
ServiceLocationProtocol(SLP)allowstheswitchtoprovidedynamicdirectory
servicesthathelpsusersfindserversbyatt ributesratherthanby nameoraddress.
SLPeliminatestheneedforausertoknowthenameofanetworkhostsupporting
aservice.SLPallowstheusertobindaservice
descriptiontothenetworkaddress
oftheservice.
ServiceLocationProtocolisdescribedinRFC2608.
Note: SLPisnotsupportedontheinternalmanagementport(MGT).
SLPdefinesspecializedcomponentscalledagentsthatperformtasksandsupport
servicesasfollows:
 UserAgent(UA)supportsservicequeryfunctions.Itrequestsservice
informationforuserapplications.TheUserAgentretrievesserviceinformation
fromtheServiceAgentorDirectoryAgents.AHostOn‐Demandclientisan
exampleofaUserAgent.
 ServiceAgent(SA)providesservi ceregistrationandservice advertisement.
Note: Inthisrelease,SAsupportsUA/DAonLinuxwithSLPv2support.
 DirectoryAgent(DA)collectsserviceinformationfromServiceAgentsto
providearepositoryofserviceinformationinordertocentralizeitforefficient
accessbyUserAgents.TherecanonlybeoneDirectoryAgentpresentpergiven
host.
TheDirectoryAgentactsasanintermediatetierintheSLParchitecture,placed

betweentheUserAgentsandtheServiceAgents,sotheycommunicateonlywith
theDirectoryAgentinsteadofwitheachother.Thiseliminatesalargeportionof
themulticastrequestorreplytrafficonthenetwork,anditprotectstheService
Agentsfrombeingoverwhelmedbytoomanyservicerequests.
Servicesaredescribedbytheconfigurationofattributesassociatedwithatypeof
service.AUserAgentcanselectanappropriateservicebyspecifyingtheattributes
thatitneedsinaservicerequestmessage.Whenservicerepliesarereturned,they
containaUniformResourceLocator(URL)pointingtotheservicedesired,
and
otherinformation,suchasserverload,neededbytheUserAgent.
FormoredetailsonSLPconfiguration,seetheLenovoFlexSystemFabricCN409310
GbConvergedScalableSwitchCommandReference forEnterpriseNOS8.4.
Active DA Discovery
WhenaServiceAgentorUserAgentinitializes,itcanperformActiveDirectory
AgentDiscoveryusingamulticastservicerequestandspecifiesthespecial,
reservedservicetype(service:directory-agent).ActiveDADiscoveryis
achievedthroughthesamemechanismasanyotherdiscoveryusingSLP.
TheDirectoryAgentreplieswithunicastservice
replies,whichprovidestheURLs
andattributesoftherequestedservice.

Lenovo Flex System Fabric CN4093 Specifications

General

Brand	Lenovo
Model	Flex System Fabric CN4093
Category	Switch
Language	English