DSS provides data redundancy for NAS and iSCSI across multiple servers. Below are descriptions and link to all of DSS features. You can download DSS for a 30 day evaluation period and make multiple copies to test this.
Cross Data Synchronization for the NAS environment: LAN or WAN to multiple servers.
Open-E DSS synchronize files and directories from one NAS server to another. Disaster recovery or Disk-to-Disk backup synchronization utilizes block-based data transfer that minimizes network traffic. The Enterprise version can synchronize data in both directions: the DSS can be the source and destination of files at the same time, allowing to cross-backup data on several servers.
Volume Replicationfor the iSCSI environment: LAN or WAN to multiple servers.
Open-E DSS provides an extra layer of fault tolerance as you mirror two iSCSI target volumes, similar to disk mirroring (RAID1). By allocating one iSCSI target as the primary data storage device and the second as a destination iSCSI target, data will synchronously be written to both iSCSI targets using a dedicated network connection. The primary iSCSI target will be replicated in real time, so that the data will be available if the primary storage system becomes unavailable.