Running iqunload in database migration mode (iqunload -au) performs the actual database migration from IQ 12.x to Sybase IQ 15.1. This mode does not use your existing IQ 12.x servers. Instead, database migration mode uses a special bundled IQ 12.7 ESD 5+ server called iqunlspt.
Running iqunload -au performs the following tasks:
Starts your old database with the iqunlspt database engine
Performs internal database checks
Determines if the database is a MPX write server
Generates the schema (similar to schema unload mode)
Starts the Sybase IQ 15.1 server
Creates a new database
Applies the generated schema
Backs up the operating system files. (This does not use the SQL BACKUP statement.)
“Understanding iqunload” for information about prerequisites, syntax, and examples for using the iqunload utility in both modes.