This error generally occurs in UNIX because the environment variable DB2INSTANCE is not set and exported before the OOB Server is started. You need to either:
 edit /usr/local/easysoft/oob/server/server and add
before the cd at the end of the file or
 defined DB2INSTANCE and export it before starting esoobserver
Alternatively, if you are using the unixODBC driver manager you can use SQL_ATTR_UNIXODBC_ENVATTR in the odbc.ini file (see elsewhere in this FAQ) to set environment variables per DSN.
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