beautypg.com

HP Hitachi Dynamic Link Manager Software User Manual

Page 208

background image

The explanation for the following sub-parameter describes how to specify

the checking interval.

-intvl checking-interval

Specify the checking interval between path health checks. Specify a

value from 1 to 1440 minutes depending on the user environment.

When you change the checking interval, the new setting takes effect

immediately. When the checking interval is shortened and the

checking interval after the change (from the end of the previous path

health check) has already elapsed, the path health check will start

over.
The path health check interval setting remains stored in the system

even if you disable the function by changing the path health checking

to off. Therefore, when you re-enable path health checking and do

not change the interval, the path health interval stored in the system

is used.

-afb {on [-intvl checking-interval]|off}

Enables or disables automatic failbacks.
on: Enabled
off: Disabled
Enabling automatic failbacks might automatically place paths online that

were intentionally placed offline (for example, paths placed offline for

maintenance work).
If you want to prevent such paths from automatically being placed online,

disable this function. When intermittent errors occur in paths or storage

systems, statuses of paths alternates between the online and offline

status frequently, thus decreasing I/O performance.
Automatic failbacks are performed on the following types of paths:

¢

Paths where an error occurred and for which the KAPL08022-E

message was displayed.

¢

Path where an error occurred during the startup of the HDLM

manager.

To prevent intermittent errors from deteriorating I/O performance, we

recommend that you also enable intermittent error monitoring when the

automatic failback function is enabled. Intermittent error monitoring is

specifiable only when automatic failbacks are enabled.
See

Table 6-5 Relationship Between the Setting for the Automatic

Failback Function and Intermittent Error Monitoring and the Executable

Operations on page 6-24

for the relationship between automatic

failbacks and intermittent error monitoring.
When you specify on, specify the checking interval by specifying the

parameter immediately following on. If you do not specify a checking

interval, path statuses will be checked in the following way:

¢

When the checking interval has not been specified before:
Every minute (default setting)

¢

When the checking interval has been specified before:

6-20

Command Reference

Hitachi Dynamic Link Manager User Guide (for Windows(R))

This manual is related to the following products: