The vxstat command can be used to check if replication is being written to the secondary server. The vxstat utility has keywords and operands for displaying statistics for dynamic disks, dynamic volumes, and subdisks of dynamic volumes. It can also display statistics at specified intervals and for a specified number of times. From a command prompt, simply type vxstat to get a list of available options:

vxstat [-g<DynamicDiskGroupName>] [-s] [-d] [-v][-i<Interval>] [-c<Count>] [<Object>...]

In the following examples, vxstat is gathering information from the dynamic diskgroup VVRDG on the secondary server at 5-second intervals. The output statistics may also be redirected. For example, vxstat -gVVRDG -i 5 > c:\vxstat_<secondary_server>.txt.

Figure 1 illustrates no activity on a secondary server, while Figure 2 displays read and write activity, confirming that replication is active.

Figure 1 - No Replication
 

Figure 2 - Active Replication
 

The output statistics displayed are as follows:

1. Read Requests/Second - The number of read requests per second for selected storage objects.

2. Write Requests/Second - The number of write requests per second for selected storage objects.

3. Read Blocks/Second - The amount of read request data (in blocks per second) that is processed for selected storage objects. It is the throughput on the read requests made.

4. Write Blocks/Second - The amount of write request data (in blocks per second) that is processed for selected storage objects. It is the throughput on the write requests made.

5. Average Time/Read Block - The average time, in microseconds, that it takes to process a read block from the time a request is made until the data is returned.

6. Average Time/Write Block - The average time, in microseconds, that it takes to process a write block from the time a request is made until the data is returned.

7. Queue Depth - The current number of read and write requests in the queue for selected disks. It does not apply to volumes and subdisks.