![System tables and multiplex dbspace management [CR 375326]](arrow-right.gif){kind=icon}
Any multiplex where all servers are not at the same version is mixed-mode multiplex. Upgrading Sybase IQ from version 12.5 to 12.6, for example, typically results in a mixed-mode multiplex for a short period.
Please see “Before You Install” in the Sybase IQ Installation and Configuration Guide Chapter 1 for details about running multiple IQ Agents on a mixed-mode multiplex.
The following operations are not recommended on mixed-mode multiplexes:
Creating a local store
Creating a local store succeeds on a 12.6 query server but not on the write server and is, therefore, lost at the next synchronize.
Creating a main store
The create operation succeeds but displays a warning. The space cannot be deleted explicitly from any 12.6 query server. The query servers that still define the deleted main store will continue running, but once stopped will not restart without override flags, and a file_id mismatch between write and query servers causes subsequent main store creates to fail.
