High Availability

SAP Sybase IQ Multiplex is a highly available system.

As with any system, failures are possible on any node. A multiplex with many nodes improves service availability should one or more nodes fail, because the work load can transfer to other participating nodes.

Many SAP Sybase IQ multiplex features can help you build and maintain systems with high service availability. Among these are coordinator failover, transaction resiliency, and the use of logical servers to isolate read-only query workload.

• Reader Node Failure
  Failure of software, hardware, or local disk on a reader causes a temporary outage for connected clients.
• Writer Node Failure
  Failure of software, hardware, or local disk on a writer causes a temporary outage for connected clients. Read-write operations are rolled back on the failed node.
• Coordinator Failure
  If the current coordinator node fails, or must be shut down for maintenance, clients on other nodes can be affected. Read-write operations are rolled back on the failed node.
• SAN or Shared Disk Failure
  These failures are the most serious because they can cause outage for all multiplex nodes.