How A Server Responds To Failure In The Boot Lun Path - EMC QLogic User Manual

How a Server Responds to Failure in the Boot LUN Path

Table 3-1
Configuration Server State
2 or more HBAs, Windows running
failover software
Windows booting
Power up
1 HBA, failover Windows running
software
Windows booting
Power up
1 HBA, no Windows running
failover software
Windows booting
Power up
Explanations of Entries
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.
Server Response to Failure in the Boot LUN Path (Single Fault)
HBA Failure Switch Failure
Multipath STOP error
Halt Halt
Multipath No Boot
STOP error STOP error
Halt Halt
No boot No boot
STOP error STOP error
Halt Halt
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.
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.)

How a Server Responds to Failure in the Boot LUN Path

Configuring an EMC Boot Device
Boot Boot
SP/Director SP/Director
Port Failure Failure
a
Multipath Trespass
Halt Halt
a
Multipath Manual
Trespass Trespass
Halt Halt
Manual Manual
STOP error STOP error
Halt Halt
No boot No boot
Catastrophic
Storage
System Failure
b
STOP error
Halt
No Boot
b
STOP error
Halt
No boot
STOP error
Halt
No boot
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