Viewing Remote Replication Pairs
This section describes how to view information about existing remote replication pairs and monitor their status.
Context
- On the remote replication pair management page, click
to refresh remote replication pair information.
- On the remote replication pair management page, click
or
next to a parameter, and enter a keyword or select a value to search for the desired remote replication pairs.
- On the remote replication pair management page, click
and select the remote replication pair parameters you want to view.
Procedure
- Choose Data Protection > Protection Entities > LUNs > Remote Replication Pairs.
Alternatively, perform any of the following operations to view the remote replication pair information:
- Choose Services > Block Service > LUNs. Click the name of the desired LUN. On the page that is displayed on the right, click the Protection tab, and then select Remote Replication from the drop-down list.
- Choose Data Protection > Protection Entities > LUNs > LUNs. Click the name of the desired LUN. On the page that is displayed on the right, click the Protection tab, and then select Remote Replication from the drop-down list.
- Choose Data Protection > Protection Entities > LUNs > LUNs. If the value of Remote Replication Pairs is not 0, click the value.
- In the function pane, view the replication pair information. Table 5-1 describes the parameters.Table 5-1 Remote replication pair parameters
Parameter
Description
Local Resource
Name of the local resource.
Remote Resource
Name of the remote resource.
ID
ID of a remote replication pair.
Remote Device Name
Name of the remote device.
Remote Device ESN
ESN of the remote device.
Local Resource Role
Indicates whether the local resource of a remote replication pair is the primary resource. If the local resource is the primary resource, it displays as Primary. Otherwise, it displays as Secondary.
Health Status
Health status of a remote replication pair. Possible values are Normal and Faulty.
Running Status
Running status of a remote replication pair. Possible values are as follows:
- Normal: Data of the pair has been synchronized.
- Synchronizing: Data of the pair is being synchronized.
- Split: The pair is in the split state, and data synchronization is suspended.
- Interrupted: The remote replication internal I/O error or the replication link is down, and you cannot perform the synchronization operation temporarily.
- To be recovered: After the remote replication internal I/O error is rectified or the replication link is up, and if Recovery Policy is set to Manual, the pair enters this state. You need to manually start data synchronization for the pair.
- Invalid: The pair cannot be used and restored, except deleting it. You must delete the pair on both primary and secondary storage devices. Otherwise, the pair creation may fail.
- Standby: A standby asynchronous remote replication CG functions as the secondary resource in a DR Star trio.
Owning Remote Replication CG
Name of the CG to which a remote replication pair belongs.
Replication Mode
Data replication mode. Possible values are as follows:- Synchronous: When data is written to the primary resource, the write request is also sent to the secondary resource. The host receives a write success message only after the data is written to both primary and secondary resources successfully, ensuring that data on the primary resource and secondary resource is synchronized in real time.
- Asynchronous: After data is written to the primary resources successfully, the host receives a write success message. Meanwhile, the primary site records the differences between the written data and the secondary resource data. Then the changed data recorded by the primary site is synchronized to the secondary site, minimizing the write latency for upper-layer applications.
Recovery Policy
Determines how data is synchronized after an internal I/O error or a replication link fault is rectified. Possible values are as follows:
- Manual: Data must be synchronized manually. The pair enters the To be recovered state.
- Automatic: The system automatically synchronizes data. The pair enters the Synchronizing state.
Secondary LUN I/O Timeout Interval
If data on the primary LUN fails to be written to the secondary LUN after the timeout interval, the remote replication pair enters the disconnected state.
Speed
Data synchronization speed.
- Low: Data synchronization takes a relatively long period of time. This value is used when the service load is heavy. The speed is normally from 0 MB/s to 5 MB/s.
- Medium: Data synchronization takes a relatively short period of time. This value is used when the service load is relatively heavy. The speed is normally from 10 MB/s to 20 MB/s.
- High: Data synchronization takes a short period of time. This value is used when the service load is relatively light. The speed is normally from 20 MB/s to 70 MB/s.
- Highest: Data synchronization takes the shortest period of time. This value is used when the service load is light. The speed is normally above 100 MB/s.
- If Speed of a remote replication pair is set to Custom, the customized data synchronization speed is displayed. The value ranges from 1 MB/s to 1024 MB/s.
Primary Resource Data Status
Status of data in the primary resource. Possible values are as follows:
- Consistent: data status of the primary resource. In normal states, it is Consistent.
Secondary Resource Data Status
Status of data in the secondary resource. Possible values are as follows:
- Synchronized: Data has been synchronized between primary and secondary resources. This value is available only for synchronous remote replication. For asynchronous remote replication, after data is synchronized between primary and secondary resources, the value is Consistent.
- Consistent: Data in the secondary resource is a copy of the data in the primary resource (at the time when the latest successful synchronization starts). At this time, data in the secondary resource is available but not necessarily the same as the current data in the primary resource.
- Inconsistent: Data in the secondary resource is not a copy of the data in the primary resource (at the current point in time or at the time when the previous synchronization ends). In this state, data in the secondary resource is unavailable. You can synchronize the data to ensure data consistency between primary and secondary resources.
Link Compression
Indicates whether data is compressed during data synchronization for the CG. Enabling link compression saves the bandwidth of replication links and improves replication performance. Possible values are as follows:- Yes
- No
Compression Status
If the status displays as Valid, data compression transmission is available for remote replication. If the status displays as Invalid, data compression transmission is not available or data compression transmission is not selected for remote replication.
Status of Secondary Resource Protection
Indicates whether protection for secondary resources is enabled. Once protection for the secondary resource of a remote replication pair is enabled, the application server cannot modify data of the secondary resource, ensuring data security.
DR Star Trio ID
ID of the owning DR Star trio.