IBM Informix Dynamic Server (IDS) databases reside in “dbspaces”, each composed of one or more “chunks” (files, logical volumes or whole disk devices). If the storage infrastructure is being upgraded, you might find that moving chunks via backup & restore or external copy would take longer than the outage window allows, particularly if this is between different sites. This article describes a method of achieving this with only a very short downtime using Informix chunk mirroring. We call it Informix Storage Migration via Mirroring:

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Abstract

In this series of articles we are exploring some of the lesser known, but still useful, commands hidden away in your Informix bin directory. The article explores the onclean utility. It’s often necessary to run more than one database instance on a single server. While this is a useful feature and quite easy to do with IDS, when things go wrong, it’s not always straightforward to tie each oninit binary back to a particular instance, and killing the wrong binary or shared memory segment can be disastrous. Since IDS 11, the onclean utility has been bundled with the server; this useful little program can help take some of the pain out of cleaning up an instance that has not shut down properly, killing only the relevant server processes, and dropping any attached shared memory segments.

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Abstract

The ‘unload’ command is not part of SQL, it is functionality built into dbaccess, other command line utilities and some GUI tools. This article shows how to extract data to a flat file directly from SQL in your application code (for instance), but only in version 11.50.xC6 or later.

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Abstract

In cases where a simple IBM Informix Primary / HDR Secondary server pair exists, it may be considered unnecessary to implement Informix Connection Manager to manage switching between the two, as OLTP applications can simply connect to whichever is the active Primary in a group defined in the sqlhosts file. This article describes a unique method for connecting appropriate applications to the active HDR Secondary in this scenario.

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Abstract

Depending on your IDS version, you may be unable to restore a test instance from production using “ontape” if the edition (Ultimate/Enterprise, Growth/Workgroup or Innovator) is different, even if the version is otherwise the same. This article provides a solution.

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Abstract

IBM Informix can use STDIO for TAPEDEV when performing backups / restores, which can be utilised to “pipe” backup data across to a target IBM Informix server, obviating the need for an intermediate file on disk. The following shows how this can be used for performing a quick copy of an IBM Informix instance.

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