In the Xorcom implementation of RAID1, two hard disks are supplied.
The diagram at the top of the page illustrates RAID1 with the two disks (Disk 0 and Disk 1) over one logical volume, with all blocks replicated/mirrored from Disk 0 to Disk 1. If the active hard disk fails, the second hard-disk automatically takes over and an alarm e-mail is sent to the system administrator. The Xorcom XE2000 IP-PBX or XE3000 IP-PBX unit continues to work seamlessly, and the system administrator can schedule a planned replacement of the faulty disk at a convenient time.