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SURVIVAL OF THE FITTEST DECnet in an IP-only World. John Marshall Riverwillow Pty Ltd. What Problem Are We Trying to Fix?. Company relies upon DECnet for Client/Server and Peer-to-Peer Applications across its WAN
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SURVIVAL OF THE FITTESTDECnet in an IP-only World John MarshallRiverwillow Pty Ltd
What Problem Are We Trying to Fix? • Company relies upon DECnet for Client/Server and Peer-to-Peer Applications across its WAN • Addition of IP systems and applications means that the company either has multiple WAN circuits or runs multi-protocol WAN circuits • Management wants to reduce network costs and standardize on an IP-only WAN John Marshall - Riverwillow Pty. Ltd.
What Happens to Our DECnet Applications? • Re-write to use IP protocols? • Can you find the source code? the programmer? • Replace (all) with IP-capable applications? • Centralize all DECnet hosts onto a single LAN? • Configure DECnet to use the IP transport? • No need to touch applications! John Marshall - Riverwillow Pty. Ltd.
DECnet Is…? • DECnet-Plus • DECnet Transport • OSI Transport • IP Transport John Marshall - Riverwillow Pty. Ltd.
DECnet Is…? Application Layer Presentation Layer Session Layer Transport Layer Transport Layer DECnet Network Layer Network Layer IP Data Link Layer Data Link Layer Physical Layer Physical Layer John Marshall - Riverwillow Pty. Ltd.
DECnet Session Control Applications • FAL (17) • MAIL (27) • PHONE (29) • NOTES (33) • CTERM (42) • …and others • All still work! John Marshall - Riverwillow Pty. Ltd.
What Do We Need? • DECnet-Plus • TCP/IP Services (Compaq or other vendor) • Must include PWIP driver • (Examples in following slides use:) • OpenVMS VAX V7.1 • DECnet-Plus V7.1 ECO 6 • UCX V4.2 ECO 4 John Marshall - Riverwillow Pty. Ltd.
How Do We Get Started? • SYS$MANAGER:UCX$CONFIG.COM • [4] Optional Components • Configure PWIP Driver (for DECnet-Plus and PATHWORKS) • SYS$MANAGER:NET$CONFIGURE.COM • [2] Change Naming Information • Include DOMAIN Directory Service • Supply IP FQDN and Address • [4] Configure Transports • Configure OSI Transport • Run OSI Applications over TCP/IP • Run DECnet over TCP/IP John Marshall - Riverwillow Pty. Ltd.
How Do We Make It Transparent? • Resolve Addresses from Simple Names • Resolve Addresses to Simple Names • Add new UAF PROXY records John Marshall - Riverwillow Pty. Ltd.
DECnet Name Resolution • Common Directory Interface (CDI) • Interface between DECnet Session Control and any configured Directory Services • DECdns • LOCAL • DOMAIN John Marshall - Riverwillow Pty. Ltd.
DECdns Directory Service • DEC Distributed Name Service • DECnet and OSI Name/Address/Synonym • Implemented via DECdns Servers • Maintained via DECNET_REGISTER.EXE • Full Name: DECUSOZ:.syd.vms01 • Node Synonym: VMS01 • DECnet Address: 62.606 • $ type DECUSOZ:.syd.vms01::PUBLIC:fred.txt • $ type VMS01::PUBLIC:fred.txt • $ type 62.606::PUBLIC:fred.txt John Marshall - Riverwillow Pty. Ltd.
LOCAL Directory Service • LOCAL Name Service • DECnet and OSI Name/Address/Synonym • Implemented via per-node/cluster database • Maintained via DECNET_REGISTER.EXE • Full Name: LOCAL:.vms01 • Node Synonym VMS01 • DECnet Address: 62.606 • $ type LOCAL:.vms01::PUBLIC:fred.txt • $ type VMS01::PUBLIC:fred.txt • $ type 62.606::PUBLIC:fred.txt John Marshall - Riverwillow Pty. Ltd.
DOMAIN Directory Service • Internet Name Service (DNS/BIND) • Internet Name/Address • Implemented via DNS Servers/Local Host Files • Maintained via UCX or text editors (edt/tpu/vi) • Full Name: DOMAIN:.vms01.syd.decusoz.com • IP Address: 123.123.4.51 • $ type DOMAIN:.vms01.syd.decusoz.com::PUBLIC:fred.txt • $ type 123.123.4.51::PUBLIC:fred.txt John Marshall - Riverwillow Pty. Ltd.
CDI Search Path Templates • Allow us to query directory services using simple names • Session Control John Marshall - Riverwillow Pty. Ltd.
CDI Search Path Templates • Applying • “vms01” • to the template • “LOCAL:.*” • Will lookup “LOCAL:.vms01” and return DECnet address 62.606 John Marshall - Riverwillow Pty. Ltd.
CDI Search Path Templates (DOMAIN) • Applying • “vms01” • to the template • “*.syd.decusoz.com” • Will lookup “vms01.syd.decusoz.com” and return IP address 123.123.4.51 John Marshall - Riverwillow Pty. Ltd.
CDI Search Path Templates • DOMAIN (Reverse) Lookup of 123.123.104.52 • Results in “vms02.mel.decusoz.com” • If we have the DOMAIN template “*.mel.decusoz.com” in the CDI Search Path, CDI will return the simple name “vms02” to DECnet John Marshall - Riverwillow Pty. Ltd.
CDI Search Path Templates • Default DOMAIN templates supplied by NET$CONFIGURE will include the DNS domain of the local host • Custom templates can be added via NET$SEARCHPATH_LOCAL.NCL(in SYS$MANAGER) John Marshall - Riverwillow Pty. Ltd.
CDI Search Path Templates • With valid CDI Search Path templates… • $ type vms01::PUBLIC:fred.txt • Will return a network address from the directory service with the first match • Will connect to DECnet on the remote node via the corresponding transport John Marshall - Riverwillow Pty. Ltd.
IP Local Host File • If a node is defined in the IP Local Host file with a simple-name alias, CDI will use the simple name even if there is no corresponding DOMAIN template maskUCX> set host vms02.mel.decusoz.com –/address=123.123.104.52 –/alias=vms02 • Useful if your network does not have a DNS server or if you have DECnet systems in many different IP subdomains John Marshall - Riverwillow Pty. Ltd.
If DOMAIN Directory Service is Not Configured • Connection is still possible but via IP address onlyNo DOMAIN Directory Service John Marshall - Riverwillow Pty. Ltd.
How Do We Make It Transparent? • Resolve Addresses from Simple Names • Resolve Addresses to Simple Names • Add new UAF PROXY records John Marshall - Riverwillow Pty. Ltd.
UAF PROXY Records • Specify the Full Name of the Remote Host • UAF> add/proxy –vms02.mel.decusoz.com::john john/default • Incoming connections do not use cluster alias IP address • Need to add PROXY entries for individual nodes in remote cluster John Marshall - Riverwillow Pty. Ltd.
Can DECnet Applications Tell the Difference? • No • Unless you are not resolving to simple names • Or unless you explicitly test SYS$REM_NODE_FULLNAME John Marshall - Riverwillow Pty. Ltd.
Can I Tell the Difference? • If you’re keen!Transport Discovery 1Transport Discovery 2 John Marshall - Riverwillow Pty. Ltd.
What Tools Do We Have? • CDI$TRACE.EXECDI Trace • DECNET_REGISTER.EXEDECnet Register • NCL • DCL • UCX John Marshall - Riverwillow Pty. Ltd.
What are the Obstacles? • Fear of DECnet-Plus • Fear of NCL • Fear of IP • Your company’s DNS subdomain structure John Marshall - Riverwillow Pty. Ltd.
Beware! • Troubleshooting can be difficult if you forget that CDI maintains a cache. • To Flush the CDI Naming Cache • NCL> flush session control naming cache entry “*” • CDI$TRACE.EXE is your friend CDI Trace John Marshall - Riverwillow Pty. Ltd.
QUESTIONS? John Marshall - Riverwillow Pty. Ltd.
Useful Links • http://www.compaq.com/info/spd/ • http://www.openvms.compaq.com/doc/index.html • mailto:John.Marshall@riverwillow.com.au John Marshall - Riverwillow Pty. Ltd.