Aix shared open function, Retry reserved-volume function, Supported os and os versions – HP XP P9500 Storage User Manual
Page 38: 38 retry reserved-volume function, Shared volume and data exchange version
AIX Shared Open Function
To share Data Exchange volumes on multiple AIX operating systems:
•
For Data Exchange versions 01-xx-59 and earlier, when one AIX OS opens a Data Exchange
volume, the other AIX OS cannot open the Data Exchange volume. This is because the AIX OS
reserves the Data Exchange volume when it opens it.
•
For Data Exchange 01-xx-60 and later, it is possible to share a Data Exchange volume across
multiple AIX operating systems by specifying the environment variable FAL_NO_RESERVE.
on page 38 shows the relationship between shared volumes and Data Exchange versions.
For AIX 4.3.1 or later (32-bit), you cannot transfer over 2 GB data (AIX restriction).
Table 6 Shared Volume and Data Exchange Version
Description
Version
Object
Cannot open a shared volume from multiple AIX systems.
01-xx-59 and earlier
FAL for AIX
(32/64 bit)
Can open a shared volume from multiple AIX systems by
specifying the environment variable.
01-xx-60 and later
To define environment variables:
•
By specifying the environment variable (FAL_NO_RESERVE), you can select shared open or exclusive
open.
on page 38 shows the relationship between the environment variable
(FAL_NO_RESERVE) and open mode.
Table 7 Environment Variable (FAL_NO_RESERVE) and Open Mode
Open Mode
FAL_NO_RESERVE
Exclusive Open (Original mode)
No definition of environment variable
Shared Open
ON
Exclusive Open
OFF
Exclusive Open
Other
Retry Reserved-Volume Function
When Data Exchange sends data to volume reserved by another system, an OS system error can
occur. The retry reserved-volume function can retry sending data to the reserved volume by specifying
wait time and retry count in an environment variable. Data Exchange can resend the data when the
reserved volume is released by the other system.
Supported OS and OS Versions
on page 39 shows the supported OS and OS versions. HP-UX does not issue the reserve
function because HP-UX does not generate a system error when it accesses a reserved volume, and
the device driver of HP-UX retries to access the reserved volume.
About Data Exchange Operations
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