Vanguard Managed Solutions 6500 PLUS Multiprocessor Nodes, Node Example, Operation

	Installing Nodes in Modulus Enclosures
Multiprocessor Nodes
Introduction
	A node based on the 6507PLUS or the 6525PLUS processor card can contain more than
	one processor card to improve reliability and availability. The two processor cards
	provide backup support to each other.
Multiprocessor
	Figure 2-7shows a multiprocessor node where an enclosure is configured for two
Node Example	6507PLUS or two 6525PLUS cards.

Slot 1	Slot 2	Slot 3	Slot 4
	Processor 2
Processor 1		Universal I/O 1	Universal I/O 2
				Slot 5
				Async I/O

	Figure 2-7. Multiprocessor Node
Operation
	This is how a multiprocessor node operates under normal conditions, with both
	processors working.

• Processor 1 handles the I/O interrupts from its own six on-board ports. The processor card in the lowest-numbered slot is the master. In Figure 2-7,Processor 1 is the master processor.

• Processor 2 handles its own on-board interrupts plus those from universal I/O cards 1 and 2 and the asynchronous I/O card.

• If Processor 2 fails, the node restarts and Processor 2 is disabled. When a processor card is disabled, interrupt requests generated by cards to the right pass to the processor card on its left. While overall throughput is reduced, links to the right of the failed processor are restored automatically.

Installation 2-29