EMC QLA23xx, QLA22xx manual How a Server Responds to Failure in the Boot LUN Path

3

Configuring an EMC Boot Device

How a Server Responds to Failure in the Boot LUN Path

Failure in the path to a SAN-based boot LUN can halt Windows in a fatal error condition. Depending on the failure, Windows may be able to transfer control to another path and continue.

Table 3-1 shows server reactions to failures in different components.

			Table 3-1	Server Response to Failure in the Boot LUN Path (Single Fault)
							Boot	Boot	Catastrophic
		Configuration	Server State		HBA Failure	Switch Failure	SP/Director	SP/Director	Storage
							Port Failure	Failure	System Failure
		2 or more HBAs,	Windows running		Multipath	STOP error a	Multipath	Trespass b	STOP error
		failover software
			Windows booting		Halt	Halt	Halt	Halt	Halt
			Power up		Multipath	No Boot a	Multipath	Manual	No Boot
		1 HBA, failover	Windows running		STOP error	STOP error	Trespass	Trespass b	STOP error
		software
			Windows booting		Halt	Halt	Halt	Halt	Halt
			Power up		No boot	No boot	Manual	Manual	No boot
		1 HBA, no	Windows running		STOP error	STOP error	STOP error	STOP error	STOP error
		failover software
			Windows booting		Halt	Halt	Halt	Halt	Halt
			Power up		No boot	No boot	No boot	No boot	No boot
					a. Depending on the fabric configuration, if multiple switches are used, then this behavior would
					qualify under the Multipath category.
					b. CLARiiON only.
	Explanations of Entries			◆	STOP Error (fatal blue screen) — Indicates host failure and
					chance of data corruption.
				◆ No boot — Cannot boot Windows.
				◆ Halt — Windows cannot recover before system has completed
					startup. (You must reboot and follow the power-up scenario.)
				◆ Manual — Manual intervention is required to continue.
					(Typically, initiate a LUN trespass using CLI or Manager. With
					Manager, enable LUN Auto-Assignment in LUN properties.)
				◆ Multipath or Trespass — This automatic operation allows no
					disruption of service. (The delay caused by this operation may
					affect Windows stability.)
3-34		EMC Fibre Channel with QLogic HBAs in Windows Hosts