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Conference netcad::hub_mgnt

Title:DEChub/HUBwatch/PROBEwatch CONFERENCE
Notice:Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7
Moderator:NETCAD::COLELLADT
Created:Wed Nov 13 1991
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:4455
Total number of notes:16761

1479.0. "2 defmi-ma in dechub 900 wont configure??" by LARVAE::HOWLETT_T (Wot no Replies ?...) Mon Sep 26 1994 14:12

    Hi,
    I would appreciate some help
    
    My customer is trying to configure 2 * 2 port fiber cards (defmi-ma)
    in his dechub 900, using hubwatch 3.0 VMS.
    The customer is familiar with the dechub 900, and configures lots of
    them.
    
    	He wishes to set one card to connect to thin wire and to backplane
    segment A, and the second card to connect to thin wire and backplane
    segment C. He tells that that hubwatch will not do this.
    
    So does this make any sense to anyone?
    Is the configuration in some way illegal, of is this a funny in
    hubwatch?
    
	Terri
T.RTitleUserPersonal
Name		DateLines
1479.1DEFMI connects only to the 48-pin backplane flex channelNETCAD::PAGLIARORich Pagliaro, Hub Products GroupMon Sep 26 1994 14:3612
    The DEFMI and DETMI are half-height repeater modules that only plug into the
    DEChub 900's 48-pin backplane.  As such, they can connect only to the
    dedicated backplane thinwire segment and the one flex channel (aka IMB)
    that are present on the 48-pin backplane. Your customer is trying to
    connect 2 DEFMIs to two different flex channel segments. The DEChub 900
    hub manager will make one of these segements the flex channel on the
    48-pin connector. Therefore the other segment must reside on the matrix
    backplane, to which the DEFMI cannot connect.
    
    Regards,
                                                                         
    Rich
1479.2Is it and/or for IMB and Thin segmentSTROP::LAYLANDThe good die young, the wealthy stay healthy.Tue Sep 27 1994 08:0812
Hi Rich,

I'm helping Terri with this config.  Will the DEFMI
connect to either the thin segment and/or the IMB ?
ie can the IMB only be used, the thin segment be 
disconnected. The reason seems to be able to have 2  
FOIRL i/p's connecting to 2 * 32 port repeaters on
the same b/p but on different b/p segments. This requires
2 DEFMI's and 2 DETMM's.


Regards John
1479.3either/or/both/neitherNETCAD::PAGLIARORich Pagliaro, Hub Products GroupTue Sep 27 1994 10:1315
    John,
    
    The DEFMI may be connected to:
    
    	- the backplane thinwire segment only
    	- the IMB channel on the 48-pin backplane only
    	- both the backplane thinwire and the IMB 
    	- neither the backplane thinwire nor the IMB
    
    Note that when a DEFMI connects to both an IMB channel and the
    backplane thinwire segment, it interconnects those two LAN segments.
    
    Regards,
    
    Rich
1479.42 in one hub, is the problemLARVAE::HOWLETT_TWot no Replies ?...Tue Sep 27 1994 13:2211
    Hi
    Firstly, I am not trying to configure this, it was done by those who
    went before. I am just trying to get it to work.
    
    Am I right in thinking that this customer has the problem because
    he has 2 * DEFMI in the same hub and wants each to connect to the
   "thinwire" backplane and the IMB, but they want each DEFMI to connect to
   "thinwire" backplane and to different flex channels.
    
    Is our only solution to go to the 12 port DEFMM-MA?
    Terri
1479.5The problem is connecting 2 flex channels with repeatersNETCAD::PAGLIARORich Pagliaro, Hub Products GroupTue Sep 27 1994 14:1736
    RE: .2
>>  The reason seems to be able to have 2
>>  FOIRL i/p's connecting to 2 * 32 port repeaters on
>>  the same b/p but on different b/p segments.
    
    I don't understand what you mean by i/p's.
    
    RE: .4
>>  Am I right in thinking that this customer has the problem because he
>>  has 2 * DEFMI in the same hub and wants each to connect to the
>>  "thinwire" backplane and the IMB, but they want each DEFMI to connect
>>  to "thinwire" backplane and to different flex channels.
    
    I agree with your statement.  I think the real question is why does the
    customer want to connect 2 DEFMIs in the same hub to different flex
    channels if both of the repeaters are also connected to (the same)
    backplane thinwire segment?  Interconnecting the 2 backplane LAN
    segments using a repeater make both segments look like one single
    segment, which causes you to lose the traffic segmentation benefits of
    have 2 independent LAN segments. You could accomplish the same thing by
    putting 2 DETMMs and 1 DEFMI on the same backplane flex channel. 

    I need to better understand exactly what the customer is trying to
    accomplish with his/her network configuration.  Why does the customer
    want to connect to the backplane thinwire?  If the customer is going to
    the trouble of creating 2 independent backplane flex channel LAN
    segments, why doesn't he/she want to interconnect them with a
    bridge/switch (as opposed to a repeater)?  Without understanding the
    customer's requirements I am not sure that a DEFMM-MA will solve the
    problem.

    Regards,
    
    Rich
1479.6What ??STROP::LAYLANDThe good die young, the wealthy stay healthy.Wed Sep 28 1994 04:3913
Terri, the answer is in .4.  The customer can have redundant
pairs of fibre into 2 DEFMI's and these can be connected
independantly to 2 900 TM's. One via the thin-wire segment
and one via the IMB. But I believe that he may break the 
repeater rules on the pair connected via the thin-wire,
because of the extra, (not mentioned), repeater feeding 
into the DEFMI's. Hence, we have three repeaters on the thin
segment, ( or does this count as 2), and only two on 
the IMB segment.

hub900/DEFMM==fibre==DEFMI-hub90-thin b/p--DETMM+++++

Regards John