 When a hardware failure occurred in one of the zones, the affected zone was brought offline without bringing down the other zone, which continued to operate as normal.When repairs were completed, the offline zone was powered on and automatically resynchronized with the other zone, restoring redundancy.The VAXft Model 310, introduced as the VAXft 3000 Model 310, code named ""Cirrus"", was introduced in February 1990 and shipped in June.