Updating Databases Simultaineously

This note requests information on how to replicate a database in the background using Informix SE 4.x. Currently we are developing applications using Informix SE 4.0 that operate on AT&T 3B2 600G computers. In the near future we will be migrating to Informix 4.1. The 3B2 computers will be connected together via an 802.3 T- base10 lan; software running on the systems will be Informix SE Run, NFS, SQL Development, 4GL Run, and Informix I-Net. Because of the excessive cost of rapid response maintenance for the hardware used in this system, we are looking into the feasibility using the following procedures to provide a "hot" replicated copy of the database on alternative 3B2. Database actions include inserts, updates, and deletes. In the case of a hardware failure, the users would be physically transferred to alternative 3B2 and operations continue. This physical transfer can be through the serial ports or via access over a X.25 packet network (DDN). When the primary 3B2 has been restored, the database from 3B2 would be backed up and restored on the primary machine; the users transferred, and the system of replicating the data would be restarted. Key to the scenario is that there disruption to the users as they are moved from one platform to the other is minimal; it is not necessary to make this transparent to the users (e.g. in a seamless transaction processing system with full redundancy). ----------------------------------------------------------------------------- Bob Kane Internet: bob@worms-emh2.army.mil (IP 134.235.9.2) TechDyn Systems Voice: (049) 6241-75936 CMR 421, BOX 706 Fax: (049) 6241-500154 APO AE 09056