Conference netcad::hub_mgnt

    
    Sorry if this is too basic for you, but it needs to be checked.
    
    Whenever ocurrs error of the "I can change xxx" kind,
    try to change the config of other module, if you can not
    make any change in the hub config, check via the setup 
    port the community name of the hub.
    
    The community name you can check on the set-up port is
    the "read-write" community name, but every hub also
    has a non-configurable "read-only" community name that
    always is "public".
    
    If you changed the communty name to other than "public", you can still
    check the status of the hub, but can not make any changes
    in the config until you specify the correct community in
    HubWatch.
    
    Saludos desde Mexico
    Carlos Silva
     

    
    
         Well besides the standard admonishment that you SHOULD be running
    the LATEST FIIRMWARE I suspect the reason you cannot connect is because
    you have run out of backplane resources. You did not give the config
    for slots 1-4 or tell us about backplane Ethernets. Assuming that you
    have the full complement of backplane Ethernets with the current
    placement of modules the configuration would not be expected to work.
    
         There is 1 IMB on the upper connector to support Ethernet. There
    are 14 IMBs on the lower connector that are shared by Ethernet and
    FDDI. Two (2) of those on the lower connector are split between slots
    4 and 5 into what we usually refer to as IMB 11A,11B and 12A,12B. In 
    order to take advantage of these split channels you must have FDDI
    modules balanced  left and right of this split. You can check if you
    are out of resources by looking in the message box form the view
    pulldown on the front panel physical view.
    
    
         You allocation of backplane channels assuming 6 Ethernets would be
    as pictured below where E stands for Ethernet, F for FDDI and X for
    unavailable:
    
    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE Upper connector IMB
    
    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE Lower connector IMB1
    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE Lower connector IMB2
    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE Lower connector IMB#
    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE Lower connector IMB4
    EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE Lower connector IMB5
    FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB6
    FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB7
    FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB8
    FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB9
    FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB10
    XXXXXXXXXXXXXXXXXXX11AFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB11A
    XXXXXXXXXXXXXXXXXXX12AFFFFFFFFFFFFFFFFFFFFFF Lower connector IMB12B
    
    This is based on needing 2 IMBs for connection between FDDI modules.
    In your original configuration with 4 modules in a simple ring you
    need 6 channels (2x(n-1)where n is number of modules). You have seven
    channels available for FDDI so it works. When you reconfigure to a
    fully self contained dual ring in the backplane you need 8 channels
    (2x(n)where n is the number of modules). You only have 7 so it will
    not work. The way to fix it is to move 2 of the FDDI modules left of
    slot 5. That being said there is no benefit to be gained by doing this
    and not just leaving it as a simple ring. With FDDI in the DEChub 900MS
    backplane we have automatic fault tolerance so that if a module fails
    all others are reconnected across the backplane. Therefor you do not
    need the resiliency that is perceived to be gained by turning
    everything to the backplane.
    
         PLEASE see note 2340 for an FDDI configuration guideline note and
    either read it or copy the hard copie noted and read it.
    
    

                                                 
    Bezzell,
    
    
    Thanks a lot for your quick answer. Although right now I cannot move 2
    FDDI modules left of slot 5 (because we must stop the service), I think
    your recomendation is correct (we are using 6 internal Ethernet
    Lans and one internal FDDI ring).
    
    By the way, could you provide a pointer to any document related to the
    backplane connection capabilities (IMBs, etc.), I have printed 
    and read the note 2340 and haven't found any information describing the
    way/limitations to connect FDDI modules to the backplane.
    
    Thanks again for your help,
    
    
    Jose Luis Platas.

    There are two really useful documents: "DEChub Ethernet Repeater Family
    Functional Specification" and "FDDI Configuration Options", but
    unfortunately I don't have the pointers for them ...
    
    Maybe someone else might know?
    
    Jeannie