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Conference azur::mcc

Title:DECmcc user notes file. Does not replace IPMT.
Notice:Use IPMT for problems. Newsletter location in note 6187
Moderator:TAEC::BEROUD
Created:Mon Aug 21 1989
Last Modified:Wed Jun 04 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:6497
Total number of notes:27359

71.0. "Do node4 entities have to be defined in the local NCP database" by ASD::MINTZ (Erik Mintz, MS ZKO3-2/S11, dtn 381-2331) Thu Mar 08 1990 13:28

Once a DNA4 node entity is registed, is it still necessary
for it to be defined in the local system's NCP database?

I have an entity which appears, with a phase 4 address, in the output
of DIR NODE4 * command.  But when I try to show that entity with
SHOW NODE4 nodename ALL IDENT
the response is

Identifiers
AT 17-NOV-1858 00:00:00


Node does not exist or is not known to local Node.


This must be because it is not defined in the local database, but
since the information is available from config, shouldn't the
show command work anyway?
T.RTitleUserPersonal
Name		DateLines
71.1A guessCCIIS1::ROGGEBAND_ �hili��e _Fri Mar 09 1990 05:0610
    Erik,
    
    This is a just a guess, someone correct me if I'm wrong: the SHOW
    Node4 command goes through the Control FM which "drops" it straight
    through to the DECnet Phase IV AM... which tries to establish a
    connection with NML on node <whatever> and fails because node
    <whatever> is not known. The config FM is not involved at all when
    using primitives, neither is the instance data in the MIR. 
    
    �hR.
71.2DECnet Phase IV AM uses Phase IV mechanismTOOK::CAREYFri Mar 09 1990 11:4214
    
    .1 is exactly right.
    
    The DECnet Phase IV AM uses DECnet Phase IV to form links and
    interrogate nodes for information.  The NODE4 entity must be 
    specified by address, or the name must exist in the local Phase IV
    database in order for a connection to be established so that the
    request can be processed.
    
    The link establishment is done directly through the normal DECnet Phase
    IV mechanisms to cut down on overhead, so DNS is not queried.
    
    -Jim Carey
71.3INFO - config does wildcard enumerationGOSTE::CALLANDERFri Mar 09 1990 12:405
    
    Only thing to note is that if you use wildcarding at the global
    entity level (ex: NODE4 *) we do use config to expand the definition
    of the wildcard.
71.4OK, how to keep in synch?ASD::MINTZErik Mintz, MS ZKO3-2/S11, dtn 381-2331Fri Mar 09 1990 13:0420
OK, I guessed as much.  But this does create an ease of use problem
for the end user.

1) If a new node is defined only in NCP, then it is available to
   conventional applications (mail, set host, etc), and will be
   manageable by MCC.  However, it will not show
   up in a directory, or be included in wildcard commands.

2) If a new node is registered in the nameserver (perhaps by another
   instance of MCC, on a different node), but not in the local NCP databse,
   then it WILL show up in the directory, will create a failure
   in wildcard operations (because while the address is available in DNS,
   it is not used, and the entry is missing from NCP), and it
   will not be manageable by MCC.  It will obviously also not
   be available to applications.

While I understand the technical reasons behind this (performance, etc),
it does not present a clear message to end users, who after all
care about the end result, not about the implementation.