z/OS Basic Skills Information Center. Networking on z/OS

268 Pages·2010·3.7 MB·English

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z/OS Basic Skills Information Center
Networking on z/OS

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z/OS Basic Skills Information Center
Networking on z/OS
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Contents
Before you begin the topic about Couplingchannels . . . . . . . . . . . 40
networking on z/OS . . . . . . . . . vii OpenSystemsAdapter(OSA) . . . . . . . 40
HiperSockets . . . . . . . . . . . . . . 46
TheI/Ocage. . . . . . . . . . . . . . 48
Part 1. Introduction to networking on
the mainframe . . . . . . . . . . . 1 Chapter 4. Sample network
configuration . . . . . . . . . . . . 49
Chapter 1. Mainframes and networks . . 3
Requirementsforamainframenetwork . . . . . 49
Mainframes,networks,andyou . . . . . . . . 3 Example:theZOSCompanydatacenter. . . . . 49
Networksandonlinesystems. . . . . . . . . 4 Keymainframenetworkavailabilityaspects . . . 52
Whyarenetworksimportant? . . . . . . . . 6 Hardwareavailability . . . . . . . . . . 53
Examplesofmainframe-basednetworks . . . . . 6 Softwareavailability . . . . . . . . . . 54
Technologychoicesaboundinnetworktechnology 7
Whosupportsthenetwork? . . . . . . . . . 8 Part 2. TCP/IP implementation on
Whatarethebasicelementsofanetwork? . . . . 9
the mainframe. . . . . . . . . . . 55
Overviewofmainframenetworkcapabilities . . . 9
z/OSCommunicationsServer . . . . . . . 11
SNAandTCP/IPonz/OS . . . . . . . . 12 Chapter 5. TCP/IP on z/OS . . . . . . 57
Securityinanetwork . . . . . . . . . . . 13 TheTCP/IPdaemon . . . . . . . . . . . 57
Dataprotectioninamainframenetwork. . . . 13 TheTCP/IPprofile. . . . . . . . . . . . 58
Availabilityofamainframenetwork . . . . . 14 TCP/IPProfilestatements . . . . . . . . 59
TheFTPserver . . . . . . . . . . . . . 64
Chapter 2. Network layers and Thetelnetdaemon . . . . . . . . . . . . 67
protocols review . . . . . . . . . . 15 Agoodresolverishardtofind. . . . . . . . 68
Howanapplicationsearchesforresolver
Networkingterminology . . . . . . . . . . 15
configurationinformation . . . . . . . . 69
Networklayers . . . . . . . . . . . . 15
Themulti-stackenvironment . . . . . . . 72
Physicalmedia,layer1 . . . . . . . . . . 16
TCP/IPclients . . . . . . . . . . . . . 72
Networkinterfacecard(NIC) . . . . . . . 16
Datalinklayer,layer2 . . . . . . . . . . 17
Chapter 6. TCP/IP in a sysplex . . . . 75
Ethernet . . . . . . . . . . . . . . 17
Mediaaccesscontrol(MAC)addressing. . . . 19 Computercluster . . . . . . . . . . . . 75
Networklayer,layer3. . . . . . . . . . . 19 Thez/OSsysplex . . . . . . . . . . . . 75
AddressResolutionProtocol(ARP) . . . . . 20 Cross-systemCouplingFacility(XCF) . . . . 76
Networktypes . . . . . . . . . . . . 20 WorkloadManager(WLM) . . . . . . . . 76
VirtualLAN . . . . . . . . . . . . . 22 Dynamicvirtualaddressing . . . . . . . . . 77
Networkrouting. . . . . . . . . . . . 22 Uniqueapplication-instanceDVIPA . . . . . 77
Routingtablesandprotocols . . . . . . . 24 Multipleapplication-instanceDVIPA . . . . . 80
InternetControlMessageProtocol(ICMP)and Dynamiccross-systemcoupling. . . . . . . . 81
otherlayer3protocols. . . . . . . . . . 26 Sysplexdistributor . . . . . . . . . . . . 83
Transportlayer,layer4 . . . . . . . . . . 27 Sysplexdistributorroles . . . . . . . . . 84
TransmissionControlProtocol(TCP) . . . . . 27 TCP/IPdefinitionsforsysplexdistributor . . . 85
UserDatagramProtocol(UDP). . . . . . . 29 Howworkcanbedistributedtothenetwork . . 90
Sockets. . . . . . . . . . . . . . . 29 Problemdetectionandrecoveryinthecluster . . 91
Networkapplications . . . . . . . . . . . 29 Theroutingfunctioninasysplex . . . . . . . 91
Networksecurity . . . . . . . . . . . . 30 Networkinterfacecard . . . . . . . . . 94
SystemsNetworkArchitecture(SNA). . . . . . 31
Part 3. SNA and SNA/IP
Chapter 3. Hardware connectivity on
implementation on the mainframe . 97
the mainframe . . . . . . . . . . . 33
Channelsubsystem(CSS). . . . . . . . . . 33 Chapter 7. Systems Network
Themainframechannelsubsystemandnetwork
Architecture - basics and
links. . . . . . . . . . . . . . . . . 35
implementation . . . . . . . . . . . 99
Hardwarechannels. . . . . . . . . . . . 37
Channelcommandword(CCW)channels . . . 37 WhatisSystemsNetworkArchitecture(SNA)? . . 99
©CopyrightIBMCorp.2006,2010 iii
TheevolutionofSNA . . . . . . . . . . 101 DLSwconfiguration . . . . . . . . . . 163
Subareanetworking . . . . . . . . . . . 102 EnterpriseExtender . . . . . . . . . . . 163
SNAnodes . . . . . . . . . . . . . 103 WhydoesEnterpriseExtenderuseUDP
Systemservicescontrolpoint(SSCP) . . . . 105 packets? . . . . . . . . . . . . . . 166
Subareasanddomains . . . . . . . . . 105 Classofservice(CoS)andtypeofservice(ToS) 167
Connectingsubareanodes . . . . . . . . 106 EEimplementationinnon-z/OSremotesites 168
ArchitecturalcomponentsoftheSNAnetwork . . 108 InternetconnectivityexploitationandEnterprise
Pathinformationunit(PIU). . . . . . . . . 111 Extender . . . . . . . . . . . . . . 169
HowLU-LUsessionsareinitiated . . . . . 112 AcomparisonofEnterpriseExtenderandDLSw 169
Classofservice(CoS). . . . . . . . . . 114 EnterpriseExtenderimplementation. . . . . . 170
VTAMsubareadefinitions . . . . . . . . . 114 SNA/IPconfigurationexamples . . . . . . . 172
VTAMstartoptions . . . . . . . . . . 115 EnterpriseExtenderconfiguration . . . . . 173
VTAMconfigurationlists . . . . . . . . 116 Extendedbordernodeconfiguration. . . . . 177
HowVTAMresourcesaredefined . . . . . 116 CiscoSNASwdefinitions . . . . . . . . 178
Sift-downeffect. . . . . . . . . . . . 118
SampleVTAMnetwork . . . . . . . . . 118 Chapter 10. TN3270 Enhanced . . . . 181
Introductiontothe3270terminal. . . . . . . 181
Chapter 8. SNAAdvanced 3270datastream . . . . . . . . . . . 182
Peer-to-Peer Networking (APPN) . . . 121 TN3270Enhanced(TN3270E) . . . . . . . . 184
IntroductiontoAPPN . . . . . . . . . . 121 TelnetprotocolandSNAmeet. . . . . . . 184
AdvancedProgram-toProgram TN3270Edescription . . . . . . . . . . 185
Communications(APPC) . . . . . . . . 122 AdditionalTN3270Efunctionssupportedin
AdvancedPeer-to-PeerNetworking(APPN) . . 122 z/OS . . . . . . . . . . . . . . . 186
APPCversusAPPN . . . . . . . . . . 122 WheretoplaceaTN3270Eserver. . . . . . . 187
APPNnodetypes. . . . . . . . . . . . 123 TN3270Eserverimplementation . . . . . . . 188
Low-entrynetworking(LEN)nodes. . . . . 124 TELNETPARMSstatementblock . . . . . . 188
Endnodes(EN) . . . . . . . . . . . 125 BEGINVTAMstatementblock. . . . . . . 190
Networknodes(NN). . . . . . . . . . 125 VTAMsetupforTN3270Eserver. . . . . . 191
Specializednetworknodetypes . . . . . . 127
SpecializedVTAMNodes . . . . . . . . 129 Part 4. Network operations and
Controlpoint(CP-CP)sessions . . . . . . . 132 administration . . . . . . . . . . 193
APPNdatabases . . . . . . . . . . . . 133
Topologydatabase(TOPODB) . . . . . . 134
Chapter 11. Network operational tasks 195
Directoryservicesdatabase(DSDB). . . . . 135
APPNnetworktopology . . . . . . . . . 135 Networkstartup . . . . . . . . . . . . 195
Topologydataupdate(TDU)flows . . . . . 135 VTAMstartup . . . . . . . . . . . . 196
Howdirectoryserviceslocateresourcesin TCP/IPstartup. . . . . . . . . . . . 197
APPN. . . . . . . . . . . . . . . 138 Howthenetworkisstopped . . . . . . . . 198
RoutecalculationinAPPN. . . . . . . . 143 z/OSnetworkadministratortasks . . . . . . 199
Transmissiongroup(TG)characteristics . . . 143 ExamplesofmanagingVTAM. . . . . . . 200
Classofservice(CoS). . . . . . . . . . 144 ExamplesofmanagingTCP/IP . . . . . . 203
Highperformancerouting(HPR). . . . . . . 145 ExamplesofcontrollingTCP/IPapplications 207
Rapidtransportprotocol(RTP) . . . . . . 146 Networkenvironmentdocumentation . . . . . 210
Automaticnetworkrouting(ANR) . . . . . 147
HPRheaders . . . . . . . . . . . . 148 Chapter 12. Network security . . . . 213
Pathswitching . . . . . . . . . . . . 149 Aboutsecurity . . . . . . . . . . . . . 213
Connectionnetworks. . . . . . . . . . . 149 TCP/IPsecurity . . . . . . . . . . . . 214
DependentLUrequester/server(DLUR/DLUS) 151 Industrystandardnetworksecurityfeatures . . 215
DefiningaVTAMAPPNnetwork . . . . . . 153 TCP/IPonz/OSsecurityfeatures . . . . . 220
DefiningdatasetsandVTAMstartupJCL. . . 153 TN3270security . . . . . . . . . . . . 224
CreatingdefinitionsinATCSTRxx . . . . . 153 SNAsecurity . . . . . . . . . . . . . 225
DefiningVTAMmajornodes . . . . . . . 154
Chapter 13. Network problem
Chapter 9. SNA/IP implementation . . 155
determination . . . . . . . . . . . 227
BackgroundonSNA/IPimplementation . . . . 155
Determiningthenetworkproblem . . . . . . 227
DLSwandLogicalLinkControl2(LLC2) . . . . 157
Networktoolsanddiagnosticaids . . . . . . 228
HowanLLC2connectionisestablishedovera
Common(z/OS-wide)toolsanddiagnosticaids 228
LAN . . . . . . . . . . . . . . . 157
VTAMtoolsanddiagnosticaids . . . . . . 231
Datalinkswitching(DLSw) . . . . . . . 158
TCP/IPtoolsanddiagnosticaids. . . . . . 235
HowSDLCdevicesareconnectedusingDLSw 159
VTAMproblemdetermination. . . . . . . . 239
iv IntroductiontoMainframeNetworking
TCP/IPproblemdetermination . . . . . . . 241 Notices . . . . . . . . . . . . . . 251
CommunicationsStorageManager(CSM) . . . . 244 Programminginterfaceinformation . . . . . . 252
DebuggingCSM . . . . . . . . . . . 244 Trademarks . . . . . . . . . . . . . . 253
CommandsusedtomonitorCSM . . . . . 245
Networkperformanceandtuning . . . . . . 246 Related publications . . . . . . . . 255
Part 5. Appendixes . . . . . . . . 249
Contents v
vi IntroductiontoMainframeNetworking
Before you begin the topic about networking on z/OS
This part of the z/OS® basic skills information center is intended to provide
information systems personnel with the background knowledge and skills
necessary to begin using the basic communications facilities of a mainframe-based
system. It provides a broad understanding of networking principles and the
hardware and software components necessary to allow the mainframe to
participate in a high volume data communications network.
While many of the networking concepts covered are operating
system-independent, the main emphasis is on the z/OS operating system. You are
assumed to have experience in computer system concepts, including computer
organization and architecture, operating systems, data management and data
communications, and systems design and analysis.
Abasic understanding of z/OS job control, library structure, and system libraries is
assumed. It is strongly recommended that you have already completed an
introductory course on z/OS, such as one that uses Introduction to the New
Mainframe: z/OS Basics or a comparable text.
This information does not comprehensively cover all aspects of data
communications, nor is it a reference that discusses every feature and option of the
zSeries® communications facilities.
Those who will benefit from this information include data processing professionals
who have experience on non-mainframe-based platforms, or who are familiar with
some aspects of the mainframe environment or applications, but want to learn
about the networking facilities of the mainframe environment.
©CopyrightIBMCorp.2006,2010 vii
viii IntroductiontoMainframeNetworking