Monitoring The Remote Path; Changing Remote Path Bandwidth; Monitoring Cycle Time - Hitachi AMS 2000 User Manual

Monitoring the remote path

Monitor the remote path to ensure that data copying is unimpeded. If a path
is blocked, the status is Detached, and data cannot be copied.
You can adjust remote path bandwidth and cycle time to improve data
transfer rate.
To monitor the remote path
1. In the Replication tree, click Setup, then Remote Path. The Remote
Path screen displays.
2. Review statuses and bandwidth. Path statuses can be Normal, Blocked,
or Diagnosing. When Blocked or Diagnosing is displayed, data cannot be
copied.
3. Take corrective steps as needed, using the buttons at the bottom of the
screen.

Changing remote path bandwidth

Increase the amount of bandwidth allocated to the remote path when data
copying is slower than write-workload. Bandwidth that is slow results in un-
transferred data accumulating in the data pool. This in turn can result in a
full data pool, which causes pair failure.
To change bandwidth
1. In the Replication tree, click Setup, then click Remote Path. The
Remote Path screen displays.
2. Click the check box for the remote path, then click Change Bandwidth.
The Change Bandwidth screen displays.
3. Enter a new bandwidth.
4. Click OK.
5. When the confirmation screen appears, click Close.

Monitoring cycle time

Cycle time is the interval between updates from the P-VOL to the S-VOL.
Cycle time is set to the default of 300 seconds during pair creation.
Cycle time can range between 30-seconds to 3600 seconds. When
consistency groups are used, the minimum cycle time increases. For one
group the minimum cycle time is 30 seconds, for two groups minimum cycle
time is 60 seconds, and so on, up to 16 groups with a minimum of 8
minutes.
Updated data is copied to the S-VOL at the cycle time intervals. Be aware
that this does not guarantee that all differential data can be sent within the
cycle time. If the inflow to the P-VOL increases and the differential data to
be copied is larger than bandwidth and the update cycle allow, then the
cycle expands until all the data is copied.
Hitachi AMS 2000 Family TrueCopy Extended Distance User Guide
Monitoring and maintenance
9–7