# Prerequisites

- All HPE Alletra MP Storage iSCSI ports are reachable from each of the cluster hosts
- The `multipath.conf` settings on each node should be configured as follows:

```
```
defaults {  
    find_multipaths yes  
    user_friendly_names no  
}
```
```

Before you set up Active-Active Peer Persistence (AAPP) replication, ensure that the following requirements are met:

**Supported configurations**

- Remote Copy is configured using either Fibre Channel (RCFC) or IP (RCIP).
- Replication targets are synchronous only.
- HPE Alletra MP B10000 arrays are running OS version 10.5.0 or later.
- AAPP replication supports only a 1:1 target mapping.

**Array configuration (outside VM Essentials)**

- Complete the AAPP Remote Copy configuration on both primary and secondary arrays.
- Configure replication ports and define targets on both arrays.
- Configure a Quorum Witness for the arrays.

For more information about array configuration, see HPE GreenLake for Block Storage UI 2.5 User Guide.

**VM Essentials setup**

- Add both primary and secondary arrays as Storage Servers in Infrastructure > Storage > Server.
- Create a datastore on both the primary and secondary Storage Servers.
