Sun Microsystems 6900 - Manual (Page 35)

Chapter 2 General Troubleshooting Procedures 15
Sun Proprietary/Confidential: Internal Use Only
The virtualization engine recognizes the primary (active) and secondary (passive)
pathing for the LUNs, and routes the I/O to the primary controller—unless there is
a path failure to the primary path. In that case, the virtualization engine initiates a
LUN failover and routes the I/O through the secondary path (which, in turn, goes
through the interconnect cables). Refer to
FIGURE 2-5 , which illustrates a path failure
where I/O is routed through both HBAs.
FIGURE 2-5 Path Failure—I/O Routed Through Both HBAs
In the event of a path failure after the second tier of Sun StorEdge network FC
switch-8 and switch-16 switches (or in the event that both T ports fail between the
switches), the virtualization engine forces a LUN failover of the affected Sun
StorEdge T3+ array and routes all I/O to its secondary path.
From the host side, nothing has changed: all I/O is routed through both HBAs (refer
to
FIGURE 2-5 ).
Host with HBA-0 and HBA-1
LUN0 - 10G
Active-MPDrive0
LUN1 - 10G
Active-MPDrive1
LUN0 - 10G
Active-MPDrive0
LUN1 - 10G
Active-MPDrive1
SAN
Database
MPDrive
Carved LUNs
Masking
Switch
Switch
Switch Switch
Virtualization
Engine(2) Virtualization
Engine(1)
Storage I/O
and Virtualization Engine Communications Traffic
LUN0 - 500 G
Active-Master
LUN1-500G
Passive-
Alternate Master
LUN0-500G
Passive-Master
LUN1-500G
Active -
Alternate Master
Logical
Multipath Drive
MPDrive 0
Logical
Multipath Drive
MPDrive 1
T3ES
(Master) (0A - 1P)
(Alternate Master)
(1A - 0P)
FAILURE