Grandstream HA100

The HAIOO is ideal for any business that requires an always-on, redundant
voice system by providing an automatic failover solution when paired with
two IJCM6510 IP PBXs. The device will constantly monitor the operational
status of both IJCM6510s and will automatically switch all system control to
the hot-standby secondary IJCM6510 when the primary device fails for any
reason.