Conference netcad::hub_mgnt

2717.0. "FDDI backplane problem??" by CHEFS::SMYTHI (Ian Smyth 774-6110/830-6275) Wed Sep 06 1995 14:59

	OK, before I start swapping hardware, I'd like to get the 
panel's opinion on this one.

	The situation is a DEChub 900 and two DECconc 900s (lets call
them A and B). There are no other modules (except 2 PSUs) in the hub.
I want to configure the concentrators so that Conc A has it's A port 
on the front and B port on the back. Conc B is the opposite (B to the 
front, A to the back). No problem so far. HUBwatch lets me do it.

	I then create the FDDI segment in the hub - no problem so 
far. The problem starts after I attach the either concentrator to the 
FDDI segment. the first one attaches OK but the second always fails 
with a "Connection Add Failed" message. 

	I have two other hubs with similar configurations and they're 
working fine. This hub did work until MCS replaced the MAM (the old 
one died totally). Could this be hardware related? 

	The hub is running -
			HW=F,RO=v1.1.6,SW=3.1.0
	The concentrators are running -
			HW=V2,RO=V1,SW=2.8.0

	Hubwatch is both VMS (V3.1) and Windows (4.0). Both give the 
same results.

    Resetting the MAM to factory defaults usually clears this type of
    problem.  
    
    
    

    Definitely do not use Hubwatch V4.0 for this. You are running old
    firmware, and need old Hubwatch. Using V4.0 might possibly screw things
    up enough to have caused this problem, in which case the fix is to 
    reset to factory, like -.1 said.
    
    And make sure you press the "refresh" button on the Lan Interconnect
    screen (not front panel options/refresh) before making the connections;
    this gets Hubwatch back in sync with the Hub.
    
    -Mike

	Thanks,

	Factory-setting the MAM seemed to confuse the concentrators. They 
weren't responding to pings after the reset. Removing & re-inserting the
concentrators did the trick.

regards,
	Ian