XTIVIA has a client who runs an old Informix database product, Standard Engine (SE) version 5.01.UD3, on SCO UNIX version 5.0.5. Both have been running well for at least twenty years without much in the way of outages. Over the years XTIVIA has assisted the client with small database and 4GL modifications and improvements and installed a secondary hard disk drive in the server on which to take backups of his database.
Recently the client’s system stopped working correctly. When they attempted to run a 4GL menu program it terminated immediately with error -408 “Invalid message type received from the sqlexec process” and a core file was generated. At the same time one could run dbaccess commands as the informix user, but when an attempt to unload data from dbaccess was made a -349 “Database not selected yet” error was presented, even with an explicit database selection statement included in the SQL.
I ran secheck on the database files, checked the environment variables (INFORMIXDIR, PATH and DBPATH) and the system log looking for an issue or anything that had been recently changed, however nothing looked wrong or out of place.
Eventually I looked at the file system a little more closely and noticed that the transaction log file, located in $DBPATH, was 2 GB in size. That is a magic number on a SCO’s 32-bit filesystem — the file could grow no larger. I then researched the issue and found that a transaction log file of that size could possibly generate strange behavior including core dumps. I made a backup of the file on a different drive and then zeroed out the file. Once the file was no longer too large for the file system the 4GL and dbaccess programs functioned as expected.
XTIVIA will work with this client to move their database, 4GL programs and other business-related software to a new linux server with the IBM Informix Innovator-C Edition and one of the available third-party 4GL replacements. Hopefully this client will still be running their business on Informix when they hit the next milestone: 64-bit file system limits.
XTIVIA can assist your business, large or small, with IBM Informix consulting. Check out our services at https://www.xtivia.com/services/data-management/informix/.