HP 6400/8400, User Manual

Page: 48 / 150

Behavior Point in time Setting
If cache data for a LUN exists on a partic-
ular controller, the unit will be brought
online there. Otherwise, the units are
brought online to Controller A.
On dual boot or controller resynch
All LUNs are brought online to the surviv-
ing controller.
On controller failover
All LUNs remain on the surviving control-
ler. After controller restoration, the units
that are online to Controller B and set to
Path A are brought online to Controller A.
This is a one time occurrence. If the host
then moves the LUN using SCSI com-
mands, the LUN will remain where moved.
On controller failback
The units are brought online to Controller
B.
At initial presentation
Path B - Failover/Fail-
back
If cache data for a LUN exists on a partic-
ular controller, the unit will be brought
online there. Otherwise, the units are
brought online to Controller B.
On dual boot or controller resynch
All LUNs are brought online to the surviv-
ing controller.
On controller failover
All LUNs remain on the surviving control-
ler. After controller restoration, the units
that are online to Controller A and set to
Path B are brought online to Controller B.
This is a one time occurrence. If the host
then moves the LUN using SCSI com-
mands, the LUN will remain where moved.
On controller failback
Table 13 describes the failback default behavior and supported settings when Secure Path is running
with each operating system or when MPIO 2.x or 3.x is running with Windows.
Table 13 Failback settings by operating system
Settings supported Default behavior Operating system
No Preference
Path A/B – Failover Only
Failback performed on the host
HP-UX
1
All settings allowed:
No Preference
Path A/B – Failover Only
Path A/B – Failover/Failback (recommended)
Host follows the unit Tru64 UNIX
All settings allowed:
No Preference
Path A/B – Failover Only
Path A/B – Failover/Failback (recommended)
Host follows the unit OpenVMS
EVA6400/8400 operation 48