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oninit: Not enough room in ROOT DBspace

Technote (troubleshooting)


When initializing Informix Dynamic Server, it is possible to get an error that there is not enough space in root dbspace.


During Informix Server disk space initialization (oninit -iy), you receive the following error message:

oninit: Not enough room in ROOT DBspace.
        Requested 15038K, ONCONFIG value 'ROOTSIZE' 1000K.


Disk space initialization use the values stored in the ONCONFIG configuration file to create the initial chunk for the root dbspace. During the disk initialization process, Informix Server creates reserve pages, chunk free list page, tablespaces, physical log, logical logs, sysmaster and sysutils database in the initial root chunk. If the value of ROOTSIZE in onconfig file is not big enough, the disk initialization process will fail.

Resolving the problem

  • Increase the value of ROOTSIZE in onconfig file.

    In the error message listed in the Problem section, the value of ROOTSIZE was set as 1000K in onconfig file, while the minimum requirement is 15038K. Consider adding 20000K to the suggested size to allow space for system catalog tables to be created and grow. The minimum requirement of ROOTSIZE may vary based on the default value of onconfig parameters on different IDS platform.
  • Decrease the values of ONCONFIG parameters that affect the space required in the root dbspace:


Document information

More support for: Informix Servers

Software version: 7.3, 9.4, 10.0, 11.1, 11.5, 11.7, 12.1

Operating system(s): AIX, HP-UX, Linux, OS X, Solaris, Windows

Reference #: 1198754

Modified date: 26 June 2014

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