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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

2343.0. "DECswitch 900EF FDDI Question" by GRANPA::DFAUST (Bad Things, man...) Mon Jun 05 1995 12:20

    	I have a custoemr who is building a 30 DEChub FDDI ring. All of the
    DEChubs will have DECswitch 900EF in them, and they will be attached
    to one another to create the ring (No concentrators will be involved).
    My question is what will happen is one or more of the hubs is powered
    down. My initial reaction is that the ring will wrap on the first power
    down and will segment with the second power down, but I'm not
    absolutely sure. I don't recall the DECswitch 900EF having an internal
    Optical Bypass Relay.
    
    Can anyone confirm give me a definitive answer?
    
    Dennis Faust

T.R	Title	User	Date	Lines
2343.1	Correct, no internal OBR...	NETCAD::BATTERSBY	`Mon Jun 05 1995 12:25`	11
	>> absolutely sure. I don't recall the DECswitch 900EF having an internal >> Optical Bypass Relay. >> Can anyone confirm give me a definitive answer? The DECswitch does not have an internal Optical Bypass Relay. One must purchase a separate external unit and connect it to the 6-pin MJ Optical Bypass Relay connector on the front of the DECswitch 900EF. Bob
2343.2	You're right.	NETCAD::GALLAGHER	`Mon Jun 05 1995 14:02`	19
	> My question is what will happen is one or more of the hubs is powered > down. My initial reaction is that the ring will wrap on the first power > down and will segment with the second power down, but I'm not > absolutely sure. Your initial reaction is correct. You didn't ask, but....the next release of the DEChub900 Management Agent Module (MAM) has a HUBwatch supported feature called auto-healing (or ring-patching - I'm not sure what the marketing term is). Briefly, when a module goes down (is reset, bug-checks, powered down, swapped out, is traced, etc.) the ring wraps and, if auto-healing is enabled, the hub "patches" the backplane such that the module is kept out of the ring. The ring unwraps. If the module comes back is is patched back into the ring. And I think there is a dual power cord option for customers who are concerned about the power source being a single point of failure for the hub. -Shawn